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UNITED STATES OF AMERICA. 



®l\fc WLnion Series 



Physiology and Health 



NUMBER THREE 



FOR ADVANCED CLASSES 



STUDIES OF THE HUMAN BODY AND OF THE EFFECTS 

OF ALCOHOLIC DRINKS AND NAECOTICS 

UPON LIF-E-ANe-J^EALTH 



3l 



t 




Copyright, 1890, by 

IVISON, BLAKEMAN, AND COMPANY 

publishers 

NEW YORK AND CHICAGO 



M°V2>2> 

ANNOUNCEMENT. 



Messrs. Ivison, Blakeman, and Company having 
published, under our advice and supervision, the 
Union Series of Text-Books on Physiology and Health, 
comprising — 

I. — No. 1— For Primary Classes, 
II. —No. 2— For Intermediate Classes, 
III. — No. 3— For Secondary Classes, 

We take great pleasure in endorsing the same, and in 

recommending their use as School Text-Books. They 

not only teach the important truths demanded by recent 

legislation, but teach them in language adapted to the 

comprehension of the grade of pupils for which each 

book is specified. 

MARY H. HUNT, 

National and International Superintendent Department 

of Scientific Instruction of the Woman's 

Christian Temperance Union. 

ADVISORY BOARD FOR U. S. A. 

Albert H. Plumb, D. D. 
Daniel Dorchester, D. D. 
Hon. William E. Sheldon. 
Rev. Joseph Cook. 



PREFACE. 



Most of our States and Territories now by law 
require that Physiology and Hygiene be taught in 
the Public Schools, with special reference to the 
effects of Alcoholic Drinks and other Narcotics 
on the human system. Many existing books, pre- 
pared to meet the demands of the first enactments 
on this subject, do not fulfill the requirements of 
more recent legislation. The present work is de- 
signed to teach the essential laws of health, and 
to comply fully with the most stringent provisions 
of the enactments requiring this subject taught, 
by conforming to their primary object, namely: To 
have the children instructed as to the nature of 
Alcoholic Drinks and other Narcotics, and the 
results of their use, and thus to forewarn them 
against the insidious poisons that are the constant 
cause of so much misery and crime. 

As much of Anatomy and Physiology is taught 
as is necessary to this end. But these Sciences do 



iv PREFACE. 



not usurp the space and time that belong to the 
more important aims contemplated by the require- 
ments which this book is intended to meet. 

The endeavor has been to make the physiological 
instruction clear and sufficient, — the Temperance 
teachings thorough, and as radical as the whole 
truth now revealed by modern scientific investi- 
gation. 

The work throughout has been more or less 
prepared and wholly supervised by Mrs. Mary 
H. Hunt, the Superintendent of the Department 
of Scientific Instruction of the National Woman's 
Christian Temperance Union, and the Advisory 
Committee of the same, to whom the publishers 
are under very great obligations. 

New York, February, 1890. 



CONTENTS. 



PAGE 

CHAPTER I. 

Introduction 7 

CHAPTER II. 

Bodily Wear and Repair 9 

CHAPTER III. 

Chemistry of the Body. — Food .18 

CHAPTER IV. 
Obigin and Nature of Alcohol 37 

CHAPTER V. 
Digestion 51 

CHAPTER VI. 

Absorption. — The Blood. — The Lymphatics ... 72 

CHAPTER VII. 
The Heart and Blood- Vessels. — The Circulation . . 85 

CHAPTER VIII. 
Respiration 102 



VI CONTENTS. 

PAGE 

CHAPTER IX. 
The Bones — The Joints 122 

CHAPTER X. 

Motion. — The Muscles . . . . . . - . . 142 

CHAPTER XI. 
The Nervous System 158 

CHAPTER XII. 
The Skin. — Bodily Heat . 174 

CHAPTER XIII. 
The Senses. — The Eye. — The Ear 188 



Physiology and health. 

CHAPTER I. 



INTRODUCTORY. 



1. The study of the human body is important for 
two reasons: First, because it is instructive. We find 
pleasure and profit in examining a machine ingeniously 
made for doing a certain work. The body may be said 
to be a living machine. It has many parts called organs, 
each having its own work; and these parts all com- 
bine in the various actions of a human life. The body 
is more wonderful and interesting as an object of study 
than any machine of man's making. 

2. Second, the study of the human body is important, 
because one who has the control and guidance of such 
a mechanism put into his hands ought to understand it 
thoroughly. We should not place a man in charge of 
a locomotive, or an electric battery, who knew nothing 
of their construction or their working. Still less should 
we be content to remain ignorant of these bodies whose 
management is committed to our care. We need to 
know especially how they can be kept in good health, 

7 



8 UNION SERIES, NO. S. 

and enabled to work to the best advantage. We need 
not only to receive rules to this end from others; but 
to know the principles on which these rules rest, and to 
make rules for ourselves. This knowledge is called 
the Science of Health, or Hygiene, from Hygeia, the 
fancied goddess of health. 

3. Health is that condition in which the body and 
all its parts are doing their work well. To understand 
the laws of health, we must know what is the work 
of the body and of each of its parts. This knowledge is 
called Physiology. It is plain also that to understand 
clearly the working of the parts of the body, we must 
know the form, size, and construction of those parts, and 
their relation to each other. This is called Anatomy. 
These three sciences, therefore, are closely joined together, 
and to know Hygiene you must know something of the 
other two. 

4. Our appetites were given to impel and guide us in 
supplying the needs of the body. But without knowl- 
edge these often lead us astray. We see everywhere 
people who are injuring their health by bad habits in 
eating ; by unsuitable dress ; neglect of ventilation and 
uncleanliness ; and others who are destroying themselves, 
by gratifying their appetites for enticing drinks. Many 
who use these drinks were ignorant, when they began 
this course, of the evil effects of such indulgence. The 
object of this book is to show how we may take such care 
of our bodies as will keep them in good health, and also 
to make plain the nature of alcoholic drinks and other 
narcotics, and their action on the various organs of the 
body, and thus to forewarn and forearm those who study 
these lessons against the danger of their use. 



PHYSIOLOGY AND HEALTH. 



CHAPTER II. 



WEAR AND REPAIR. 



1. Like everything else in this world, the human 
body wears out with use. Every movement that we 
make wears it more or less. Talking, and even thinking, 
wear it; and when we are as quiet as we can be, the act 
of breathing and the circulation of the blood, and other 
movements that are going on within us, are still wearing 
it away. 

2. Accordingly, the body is constantly giving off waste 
particles. The surface of the skin itself wears away. 
Perspiration passes through the skin, — about a pound 
and a half (680 grms.) daily. During the same time 
about two and three-quarters of a pound (1247 grms.) 
of carbonic-acid gas and water go out in the breath. 
The natural discharge of the kidneys and the bowels 
per day will weigh four pounds (1815 grms.). 

3. The body of a full-grown man loses in twenty-four 
hours as follows : — 

lbs. grms. 

Through the skin 1.50 ( 680) 

Through the lungs .... 2.75 (1247) 

Through the kidneys and bowels . . 4.00 (1815) 

Total 8.25 (3742) 

4. This has been learned by experiments. Of course 



10 UNION SERIES, NO. 3. 

the amount of loss would not be the same in everybody. 
Nor would there be the same loss in the same body at 
different times. If we exercise more, we perspire more 
and breathe more rapidly, and the body wears more than 
if we are quiet. But we all lose something every day. 

5. Notwithstanding this daily loss, the body of a 
healthy man continues at about the same weight from 
day to day and from week to week, because w T hat he 
loses daily is made up by what he gains. The body 
of a healthy child grows heavier, because his daily losses 
are more than made up by his daily gains. We gain 
by taking in substances which we find around us. 

6. The human body, and the bodies of the lower 
animals as well, have the wonderful power of taking 
substances into themselves and making them a part of 
themselves. The body is like a machine in that it wears 
out with use; but no machine can repair its own wear 
and waste as the body can. 

7. Those substances which the body takes in to repair 
its own wear, and to increase its size, are Foods, Drinks, 
and Air. Foods and drinks are taken into the stomach. 
Air is taken into the lungs. 

8. We cannot live five minutes without air. We 
can go without drink for several days, if necessary. 
Men have gone without food for a month. Those who 
have done this, like the famous Dr. Tanner, and others 
who have imitated him, have kept very quiet, and taken 
pains to have the daily losses of their bodies as small as 
possible. But every day they lose something more than 
they gain, and would die if they refrained from food 
much more than thirty days. Probably few people could 
live as long as that without eating. 



PHYSIOLOGY AND HEALTH. 11 

9. A healthy man, who maintains the same bodily 
weight from day to day, loses, — 

lbs. grms. 

Through the skin 1.50 ( 680) 

Through the lungs .... 2.75 (1247) 

Through the kidneys and bowels . . 4.00 (1815) 

Total 8.25 (3742) 

He gains, — 

lbs. grms. 

Through the lungs 1.50 ( 680) 

Through the stomach and bowels . 6.76 (3062) 



Total . 8.25 (3742) 

He needs about five pounds of food and drink. A 
child who is growing takes more of food and drink and 
air than his losses amount to. 

Sleep. 
II 

1. The losses and gains of the whole twenty-four 
hours are about equal. But they are probably seldom 
the same during different periods of the same length. 
When the muscles are working, they are losing faster 
than they are gaining. When they are at rest, they 
are gaining more than they are losing. So of the other 
parts of the body, and so of the body as a whole. While 
it is active, it is losing substance faster than it is gain- 
ing. While it is at rest, it is gaining substance faster 
than it is losing. 

2. If a man were placed in a balance delicate enough 
to mark the slightest change of weight, the balance would 
not remain still, but would constantly be rising and fall- 



12 UNION SERIES, NO. 3. 

ing. Every breath taken in would weigh it down, and 
every breath given out would cause it to rise. Every 
motion he made would lighten him a little, while 
every mouthful of food would make him heavier. 

3. While in various ways we rest during the day, 
the activity of the body, and especially of the brain, 
makes the losses so much in excess of the gains, that it 
is necessary for us to have during a part of each twenty- 
four hours absolute rest for repairs. This absolute rest 
is sleep. 

4. In sleep, the brain so nearly ceases to act that we 
lose our consciousness. If it thinks at all, it is only in 
the disconnected and fanciful fashion of dreams. Sleep 
has been called by the poets the " twin brother of death. " 
In it we lie unconscious, motionless, and helpless. And 
yet w T e are glad to spend one-third of our whole time 
in this deathlike state. For in sleep our bodily losses are 
made good. Waste is very much diminished, while from 
the air and from the food and drink which have been 
taken, substance is stored up for future use and we awake 
feeling fresh and strong. 

5. An infant sleeps nearly all the time during the 
first few weeks. Little children need at least ten or 
twelve hours' sleep in the twenty-four. A grown person 
should sleep from six to eight hours. It is said that 
Frederick the Great required only five hours' sleep daily, 
and that Napoleon Bonaparte, in his military campaigns, 
took only four hours daily. 1 Those who are watching 

1 Napoleon, it is said, often slept in his chair, and so caught naps 
at odd times, that added much to the sleep taken while in bed. 
But no one should attempt to follow such an example. It is too 
great a risk to health and working ability. 



PHYSIOLOG Y AND HEALTH. 1 3 

over the sick are sometimes able to go for weeks with 
but four or five hours of sleep in each twenty-four. But 
these are exceptional cases. Students and other night- 
workers may for a time be spurred by ambition or love 
of their pursuit to live with but little sleep, but they 
feel the bad effects of such a course sooner or later. The 
brain which is thus compelled to work, without its hours 
of rest, soon becomes exhausted, and the student " breaks 
down." " Nervous prostration " results very commonly 
from allowing the brain to spend more than its measure 
of strength. 

6. We are creatures of habit in regard to sleep. It 
is much easier to fall asleep, if the hour for retiring is 
always the same, than if we are irregular in this respect. 
The night is the best time for sleep, though many are 
compelled by their occupations to reverse the order and 
sleep in the day-time. Many " pleasure-seekers " turn 
night into day, a practice that is not healthful, even 
though the number of hours spent in sleep is the same. 
The light and air of day are better for action, while the 
darkness and silence of night favor repose. The custom 
of German cities, where evening entertainments begin at 
six o'clock, and the doors of all houses are locked at ten 
o'clock, is a good one. 

7. Inability to sleep is a sign of danger, and should 
always be attended to. It results from unhealthy action 
of some part of the body, and causes still further dis- 
turbance. Whatever leads to it, — overwork, or undue 
excitement, or irregularity in habit, — should be cor- 
rected at once. A warm foot-bath before retiring will 
sometimes induce sleep. Rubbing with a towel or flesh- 
brush is another method. When the evening has been 



14 UNION SERIES, NO. 3. 

spent in study, a brisk walk of fifteen minutes in the 
open air will dispose to sleep. 

8. These methods are useful, because they withdraw 
the blood away from the brain to some other part of the 
body. While the brain is active it contains a very 
large amount of blood in proportion to its size, — about 
one-fifth of the total amount in the body. When the 
time for sleep comes, the blood-vessels grow smaller, and 
the amount of blood is lessened. At the same time the 
drowsy feeling comes over us, and it is hard to keep 
from falling asleep. Observation of cases, in which a 
piece of the skull has been removed, show that while 
we are sound asleep the brain is pale and comparatively 
bloodless. 

9. In various disordered conditions, the blood-vessels 
of the brain do not contract as they should when sleep 
is needed. The blood continues to pour through in full 
tide, and sleep does not come. 

10. In delirium tremens, one of the diseases caused by 
alcohol, the excited brain is full of dreadful images, and 
sleep is banished for days, until the paroxysm ends in 
recovery or death. 

11. Since sleep is so essential to life and health, 
and since so much of our time — nearly one-third — is 
spent in sleeping, the bedroom is an important part of 
the house. It should be well supplied with fresh air. 
It should be dry. It should not be exposed to any 
noxious vapors, like those which arise from a wet cellar, 
with decaying vegetables in it; or from a cess-pool, or 
sewer, or other foul spot. One source of danger in cities 
is the pipe in the stationary wash-bowl connecting with 
the sewer. If this is not properly trapped and venti- 



PHYSIOLOGY AND HEALTH. 15 

lated, poisonous gases come up through it. Bedding 
and the clothes worn at night should be thoroughly 
aired in the day-time. 

Ill 

Object of Eating and Drinking. 

1. The object of eating and drinking is the mainte- 
nance of physical health and strength. True, it is a 
pleasure to every healthy person to eat and drink at 
proper times. The Creator has made it so, in order 
that we might never fail to do these very necessary acts. 
If we were not impelled to them by our appetites, we 
would often neglect them when w^e are absorbed in some 
interesting pursuit. But we ought not to eat or drink 
simply for pleasure. Many things are pleasant to the 
taste which are unwholesome. And we are also often 
tempted to eat too much. 

2. Each one should observe what kinds of food are 
injurious to himself, and decline them. Highly stimu- 
lating foods, alcoholic beverages, and tobacco, which 
injure the body, and do not repair its losses, should be 
absolutely avoided. 

3. Many people eat more than they need. In con- 
sequence of this, they become fat and dull; or if their 
stomachs are not strong, they suffer from a feeling of 
discomfort after meals. Such persons generally indulge 
in rich and dainty dishes, which entice them to con- 
tinue eating after their natural appetites are satisfied. 
The remedy for this is to adopt a plain diet. 

4. Many people undoubtedly eat too little. Those 
whose health is not good frequently lose their appetites, 
and need to make an effort to eat enough to repair their 



16 UNION SERIES, NO. 8. 

losses. Delicate children must sometimes be pressed to 
eat. But it is a mistake to coax them with pastry and 
sweetmeats. These, by overtaxing a weak stomach, will 
increase the difficulty. Busy men and women often 
give too little time to eating and sleeping. This is as 
poor policy as it would be for a locomotive engineer to 
drive past the station, where he should get his supply 
of coal and water, because he is in a hurry. 

Alcohol.— Waste and Repair. 

5, For many years it was considered that alcoholic 
liquors of various kinds helped in repairing the waste, 
and aided in building up the tissues of the body. Now it 
is known that alcohol is not only incapable of doing such 
things, but that its injurious action on various organs 
prevents the body from being properly nourished by real 
foods. 



QUESTIONS. 



1. What wears out the body? 

2. What evidence have we of wear and waste in the body? 
By what channels does waste matter go out of the body ? 

3. What is the daily loss of the body through each of these 
channels ? 

4. Is the amount of loss the same in everybody? Is it the same 
every day ? 

5. Why does not body-weight constantly diminish? 

6. How is the waste of the body repaired ? 

7. What substances serve to repair the waste of the body ? 

8. For what substance have we the most constant and pressing 
need? 

9. Eepeat the table of bodily losses and gains. 



PHYSIOLOGY AND HEALTH. 17 

ii 

I, 2. Do losses and gains maintain a constant balance ? 

3, What is the object of sleep? 

4, In what condition are we during sleep? 

5, How much sleep is necessary? 

6, What is the best time for sleep? 

7, What are the causes and the consequences of inability to 
sleep ? 

8, How may we induce sleep? Explain the methods. 

9, 10, W x hat diseases banish sleep? 

II. What conditions should be secured for our bedrooms? 

in 

1. What is the object of eating and drinking? 

2. What articles of food and drink should be avoided? 

3. How may we, guard against overeating? 

4. Is there any danger of eating too little? 

5. Does alcohol repair waste tissue? 



18 



UNION SERIES, XO. 3. 



CHAPTER III. 



CHEMISTRY OF THE BODY.-FOOD. 



1 . Chemistry tells us that all material things are made 
of about seventy simple substances, called " elements." 
Every object that we are acquainted with is composed 
of two or more of these elements. The chemist, in his 
laboratory, can analyze or break up into its elements any 
substance, and can tell what these elements are, and how 
much of each element there is in it. This is as true of 
animal bodies as of vegetable or mineral matter. A piece 
of meat or bone can be analyzed as well as a stone or a 
stick. 

2. So it has been found that of the chemical elements 
only fourteen enter into the human body. These are : 





Parts in 100. 




Parts in 100. 


Oxygen . 


72.00 


Calcium . 


1.30 


Hydrogen . 


. 9.10 


Sulphur 


. .1476 


Nitrogen . 


2.50 


Sodium . 


.10 


Chlorine 


.085 


Potassium . 


. .026 


Fluorine . 


.08 


Iron . 


.01 


Carbon 


. 13.50 


Magnesium . 


. .0012 


Phosphorus 


1.15 


Silicon 


.0002 



Traces of several other substances, as manganese, cop- 
per, lithium, etc., are found in the body, but they are 
not constant. 



PHYSIOLOG Y AND HEALTH. 1 9 

3. When the chemist analyzes the substances which 
we use as food and drink, he finds that they are all made 
of the same elements that compose the body. Since we 
eat for the purpose of restoring to the body what it loses 
by daily wear, it is to be expected that we should eat 
things that contain the elements that are lost. 

4. In truth, we eat no other things. The elements 
that are not found in the body do not enter into our 
foods. Gold, silver, mercury, and zinc, for example, 
are elements which are not found in the human body, 
and they poison us if they are mixed with our food, 
though they are sometimes used as medicine. 

5. All our foods and drinks are made of the same 
elements that compose the body. 

6. These elements are more abundant in nature than 
all the rest. They are found everywhere in the earth, 
in the air, and in the water, as well as in plants and in 
animals. And yet men often starve for want of them 
while they are surrounded with them. It is only as they 
are found in certain plants and animals that we can use 
them as food. There is plenty of carbon in a tree, and 
carbon is one of the needed elements. But we cannot 
eat wood. The air contains in a hundred parts seventy- 
nine parts of nitrogen, and nitrogen is absolutely neces- 
sary for the maintenance of our lives. But we cannot 
get it from the air. The lower animals can use many 
things as food which we cannot use, because they have 
powers of digestion that we have not. 

7. The food of mankind, and all the lower animals, 
must not only contain the needed elements, — it must 
contain them in the form of vegetable or animal food. 
We cannot subsist upon earth, air, or water, alone. 



20 UNION SERIES, NO. 3. 

8. And yet the elements which compose our food came 
originally from the earth, air, and water. Plants have 
the power, which animals have not, of feeding on earth, 
air, and water. They take up from these three sources 
the elements that they need, and make them a part of 
themselves and grow and thrive upon them. 

9. So the plants do the great work of preparing 
our food for us. All the food of all the lower animals 
and of man is first drawn from the earth and air and 
water by the plants. 

II 

Organic and Inorganic Substances. 

1. Of the elements already named which enter into 
the body of man, four are more abundant than all the 
rest. These four are carbon, hydrogen, nitrogen, and 
oxygen, which are indicated in chemical language by 
the letters C H N 0. Ninety-seven parts in a hundred 
of the body of man and the lower animals consist of 
CHNO. 

2. Accordingly, our food is made chiefly of the same 
four elements. The remaining elements must be had 
also. But they are united generally in small proportions 
in the different substances which make up our diet. 

3. The many and diverse articles that we eat are 
classified according to their chemical composition. The 
first grand division is into organic and inorganic sub- 
stances. The inorganic substances are those which we 
find in inanimate nature as well as in animal bodies, 
such as water, chloride of sodium (common salt), phos- 
phate of lime, and many other mineral matters. With 



PHYSIOLOGY AND HEALTH. 21 

the exception of water, these form a very minute part 
of our daily food. And water and salt are the only 
inorganic substances that we take clear. The others are 
all combined in ordinary articles of food. All fruits 
and vegetables, for example, contain phosphate of lime. 
Sulphate of sodium and carbonate of potassium are 
found in most of the grains. 

4. The organic substances in the body and its food 
are those that we do not find in inanimate nature. They 
exist only in living animals or plants. They are divided 
into two subdivisions — nitrogenous and non-nitrogenous 
— according as they contain C H N 0, or only C H 0. 

5. The foods that are chiefly nitrogenous are meats 
of all kinds. Eggs and milk are largely nitrogenous. 
The foods which are for the most part non-nitrogenous 
are all grains, vegetables, and fruits. The non-nitro- 
genous foods are again divided into starches, sugars, 
and fats. 

6. To recapitulate, we have in the body and in its food 
the following classes of substances: — 



Inorganic. 



Water. 

Salt. 

Phosphates. 
Carbonates. 
L Sulphates. 



Organic. 



'Nitrogenous, j Meat ' fish > e ^ s > milk > and other 
( animal foods. 

f Starchy foods, (as the grains, 
Non-nitrogenous. < which contain some nitrogen) 
t sugars, fats. 



22 UNION SERIES, NO. 3. 

7. In most articles of food these classes are mixed. 
Wheat, for example, contains some fat and some nitrogen- 
ous matter, with much starch. Flour, which is chiefly 
starch, contains some of a nitrogenous substance, called 
gluten. While in process of digestion, these substances 
are separated ; they are digested in different parts of the 
alimentary canal, and are acted upon by different fluids. 

Ill 

Animal and Vegetable Food. 

1. Some animals, such as the tiger, live only upon 
other animals. We call them carniverous, which means 
flesh-eating. Other animals, such as the ox, live only 
upon vegetable food. We call them herbivorous, which 
means plant-eating. The carniverous animals have teeth 
with sharp points and edges, which are fitted for cutting 
and tearing flesh. The herbivorous animals have teeth 
which are broad and fitted for grinding. Man has 
both the cutting teeth and the grinders, and this shows 
that it was designed that he should eat both animal and 
vegetable food. He is omniverous. 

Animal Foods. 

2. Milk is our earliest food, and it contains all the 
required elements so combined that it is perfectly well 
adapted to the needs of the growing infant. Bone, 
muscle, and nerve find in milk the materials which they 
need for their nourishment and growth. Milk is also 
a most valuable food in sickness, because it is usually 
easily digested. 

3. Beef, veal, pork, mutton, and poultry are the 



PHYSIOLOGY AND HEALTH. 23 

meats in general use, though many other kinds would 
make good food. 

4. Of these beef is on the whole the best. Pork and 
veal are not easily digested, and should be avoided by 
those who have weak stomachs. 

5. Fish contains the same elements as meat. It is 
less solid, and for that reason more digestible in many 
cases than flesh-meat, 

6. Eggs are very nourishing and palatable. They 
sustain the young fowl for the first period of its life, 
and contain all the elements needed for the growth of 
its body. 

7. The oyster is the most popular fish-food in North 
America. To most people it is a very palatable dish. 
Raw oysters are more easily digested than fried oysters. 

Vegetable Foods. 

8. The most important class of vegetable foods con- 
sists of the grains, — wheat, corn, oats, barley, rice, etc. 
Grains are the seeds of the plants on which they grow T . 
In them is stored up the nourishment w T hich is to 
sustain the tender germ of the plant until it becomes 
rooted, just as the egg sustains the growing chick until 
it breaks through the shell. The farmer raises the w T heat 
and the corn, and preserves the ripe seeds, and so the 
nourishment w r hich the plant, with its roots and its leaves, 
helped by the rains and the sunshine, has made out of 
earth and air and water becomes food for man. 

9. Wheat is the finest of the grains, and the best 
bread is made from wheaten flour. Rice is the principal 
food of one-third of the human race. Corn contains 
more oil than other grains. Oats, which used to be 



24 UNION SERIES, NO. 3. 

regarded as only food for horses, are now, in the form 
of oatmeal porridge, used as a part of the daily fare of 
a great number of people. Oats contain more than 
any other grain, except wheat, of the substance that 
makes muscle. Fine oatmeal, thoroughly cooked (for 
three or four hours), is a very light, digestible, and nutri- 
tious article of diet. Coarse, half-cooked oatmeal is not 
healthful food. Well-cooked mush, made of ground 
whole wheat, is the most nutritious, easily digested, 
and healthful of foods. 

10. Peas and beans contain a great deal of nutritious 
substances. They are useful for this reason in feeding 
armies and other large bodies of men. But both are 
difficult of digestion for a stomach that is not strong 
and healthy. 

11. The potato originated in South America, and is 
a comparatively new vegetable. It was not known in 
Europe until the sixteenth century, and has only been 
extensively used for the past two hundred years. Now 
it is cultivated wherever the climate will permit. It is 
light, palatable, and easily digested. 

12. There are many vegetables which are used, not 
so much for the nourishment they contain, as for their 
pleasant taste and the healthy action of their juices. 
Such are turnips, beets, lettuce, and celery. 

13. Animal food, as compared with vegetable food, 
contains a larger amount of substances containing nitro- 
gen. Nitrogen is necessary to the formation of all the 
tissues of the body, and nitrogenous food is therefore 
essential. Vegetables, on the other hand, contain a 
larger proportion of starch. Rice, for example, is 88 
per cent, starch. A mixture of animal and vegetable 



PHYSIOLOGY AND HEALTH. 25 

substances secures a proper combination of nitrogenous 
and starchy substances for healthful food. 

IV 

Fats. 

1. The custom of eating oil or butter or some purely 
fatty substance with other food is almost universal. Fat 
is supposed to be used in maintaining the heat of the 
body. It helps, too, in the digestion of other articles. 
But it must be used in moderate quantities, and it is 
often necessary for those who have weak stomachs to 
avoid it entirely. 

Sugars. 

2. Sugar is found in many plants, and is an impor- 
tant article of diet, not only for its agreeable taste, but 
for its warming and fattening properties. Children 
are always fond of sugar, and a reasonable amount is 
healthful for them; but if allowed to gratify their taste 
unchecked, they frequently use too much of it. It 
is safer to give them white sugar than to give them 
colored candies. The coloring matters are sometimes 
unhealthful. 

V 

Cooking. 

1. Fruits and some vegetables are eaten raw, but the 
most of our food is cooked. 

2. Cooking serves several ends: 

(a) It makes food more tender and digestible. The 
harder parts of meats and vegetables are softened, and 



26 UNION SERIES, NO. 3. 

the fibers are separated so that they can be more easily 
masticated or chewed, and the digestive juices can pene- 
trate them. 

(b) It develops pleasant flavors. The smell of well- 
cooked meats arouses the appetite and makes the mouth 
water, w\hile the odor of some meats uncooked would be 
repulsive. 

(c) Meats, and sometimes other foods, may contain 
parasites, which will affect those who eat them injuri- 
ously. In countries where raw meats are eaten, many 
people suffer from tape-worms. Thorough cooking is 
a perfect safeguard against this danger. 

3. It is very important that the cooking should be 
properly done. The stomach is injured by trying to 
digest poorly cooked food. 

4. If bread or cakes are "heavy," they are hard to 
digest. If meat is overdone, the nutritive juices are 
cooked out of it and we lose them. If too much fat is 
used, and especially if it is fried into food, it forms a 
coating over each particle which resists the action of 
the juices of the stomach. Good cooking makes food 
so attractive that the appetite is stimulated, and so diges- 
tion is aided. Since all our strength is derived from 
our food, the art which prepares it properly and adds 
to the pleasure of the family table, is not beneath the 
attention of any one. The custom which is prevalent 
in many places of leaving this fine art wholly to un- 
skilled servants should be abandoned. 

5. A young maiden should not only know how to 
make good bread, but she should be taught how to cook 
and prepare in a healthful and attractive manner the 
various kinds of food that are necessary to best sustain 



PHYSIOLOGY AND HEALTH. 27 

health and strength. The lad who learns to cook will 
not become less manly for having such knowledge, and 
he will thereby be better able to meet many emergencies 
that are common to every-day life. 

Baking. 

6. In order to make good bread, w T e must have — 
(1) good flour; (2) thorough kneading; (3) good yeast; 
(4) good judgment exercised in keeping the rising mass 
just warm enough and letting it rise just long enough ; 
in having the oven just hot enough, and taking out 
the bread at just the right time. 

7. Good bread is light and sweet. Bread is light 
when the carbonic-acid gas formed in the fermentation 
caused by the yeast has worked through the whole loaf, 
making innumerable holes and pores in it, When such 
bread is eaten, the digestive juices easily enter these 
pores, and spread through and act upon every part of it. 
While bread is baking the carbonic-acid gas escapes. 

8. Bread is heavy when carbonic-acid gas has not 
penetrated the mass, either because the yeast is poor 
or because it has not been thoroughly kneaded. Such 
bread makes in the stomach a solid lump, which the 
digestive juices cannot easily enter, and that organ be- 
comes weary and sore in struggling with it. 

9. Bread is sour when fermentation has gone on too 
long, in which case an acid is formed in it. 

10. Pastry and cake should be eaten only in small 
quantities, and some people should not eat them at all. 
They contain too much sugar and butter in proportion 
to other nutritive matters to be eaten freely. 



28 UNION SERIES, NO. 3. 

VI 

Mineral Substances 

1. Mineral substances are mingled with all our food. 
Salt is the only solid mineral matter that we take pure. 
It enters into every part of the body, solid or fluid, and 
aids the processes of life. 

2. Mineral substances are not commonly changed by 
digestion. 

Eating and Drinking Habits. 

3. The eating and drinking habits of mankind vary 
greatly. They are modified by the climate, and by sur- 
roundings. The Esquimaux drink fish-oil and eat candles 
with a relish. The Hindoo lives upon rice. The Arab 
supports life, and performs great journeys on a handful 
of grain a day. The European or American requires 
a better kind of food. The human body can adapt itself 
wonderfully to its circumstances. But the people of 
those nations, which, by reason of their geographical 
situation and their wealth have been able to obtain the 
best and most varied diet, have the strongest bodies. 

4. There is is also an endless variety in the habits 
and tastes of members of the same race or community. 
Some prefer one kind of food and some another. Some 
eat two meals a day and some three. Constitutions, 
habits, and circumstances make great differences. One 
man. may thrive on food that would destroy another. 
A brain-worker may accomplish most and feel best if 
he eats little until noon; a day-laborer would lose his 
vigor under such a practice. One man is overfed by a 
flesh-meat diet, while another ought to live chiefly on 



PHYSIOLOGY AND HEALTH. 29 

meats. If nature had not made mankind capable of such 
variations, the work of the world could not be done. 

5. A healthy appetite is nature's guide to right habits 
of eating and drinking. But nature intended that our 
appetites should be controlled and regulated by reason. 
Every person should adopt that course which is best 
suited for him. 

6. When large bodies of men have to be fed, as in an 
army or navy, it becomes necessary to find out just how 
much of each kind of food a man requires daily. By 
combining physiological reasonings with experiment, 
Professor Dalton found that for a man in health, taking 
exercise in the fresh, open air, the following was a 
sufficient daily ration : — 

Meat 

Bread 

Butter 

Water 

Total 92J (2623) 

Total : water, 3 lbs. 6 ounces ; solids, 2 lbs., 6J ounces. 

Men at hard labor require more, and those who are 
entirely inactive less. 

VII 

Alcohol not a Food. 

1. Alcohol contains no nitrogen, and must therefore 
be excluded from the nitrogenous foods. JWhen taken 
into the body it does not raise the temperature. On the 
contrary, it causes a reduction of bodily heat as will be 
hereafter shown (page 187). 



oz. 
16 


grms. 

( 453) 


19 


( 540) 


3J 


( WO) 


54 


(1530) 



30 UNION SERIES, NO. 3. 

2. A true food increases strength of muscle. Alcohol 
diminishes muscular strength. Sometimes, during a 
storm at sea, sailors are given rum or whisky to help 
them endure the extra hardship. For a short time after 
taking it they appear more active, but in reality are 
weaker. They cannot endure so long a strain on their 
muscular power or vitality as those working under the 
same circumstances who take no alcohol. 

3. Neither can alcohol be classed with the salts which 
regulate the passage of liquids through the tissues, nor 
with water which is the great solvent and carrier of the 
body. The action of alcohol is directly antagonistic to 
the work done by either of these. Instead of rendering 
the tissues more soft and pliable and in better condition 
for the transmission of food and waste, it hardens them. 1 
It also irritates, inflames, and may cause destructive 
changes. 

4. All true foods satisfy the appetite w r hen enough for 
the needs of the body has been taken. 2 The body needs 
no alcohol, and it is the nature of alcohol to create an 
appetite for itself that can never be satisfied. 

1 If a piece of meat be left in alcohol for a few hours it will be 
found much harder than when it was put in, because alcohol has 
taken the water from it. In certain experiments where it is desir- 
able to extract the water from dead animal substances, as the 
mucous membrane of the stomach, this is accomplished by im- 
mersing the substance for a short time in alcohol. 

2 " If a person eats bread three times a day for twenty years, he 
is just as readily satisfied at the end of the time as he was at the 
beginning. Natural appetite, or hunger, is simply the demand for 
material to supply the growth or waste of tissue. Every sub- 
stance capable of assimilation will satisfy that demand, and with 
that satisfaction, ceases for the time being, all relish for more." — 
Davis : Practice of Medicine, page 34. 



PHYSIOLOGY AND HEALTH. 31 

5. It has been laid down as a principle by eminent 
physiologists that " any substance, in order to be consid- 
ered a food, must not be injurious to the structure or 
action of any organ, otherwise it is a poison, not a food." 1 
Alcohol is injurious to the structure and action of vari- 
ous organs of the body, and therefore cannot be properly 
classed with foods. 

Till 

Natural Drinks. — Water. 

1 . Water forms about seventy of every hundred parts 
in the body. It must be constantly supplied, therefore, 
to provide for the growth and make up for the waste of 
the parts. Digestion, absorption, and circulation would 
stop without water. The craving for it is stronger than 
for food. We are therefore drinking beings, and it is 
necessary to our health and usefulness that we take the 
right kind of drinks. What these are is an important 
inquiry. The living bodies of men and the lower ani- 
mals, as we have seen, are so formed that water is the 
fluid by which their thirst is assuaged, and by which 
they may live. 

2. Water serves four important purposes in the 
body, — 

(a) It keeps the tissues moist and flexible. A piece of 
, dry glue is brittle, and will break if you attempt to bend 
it ; allow it to soak up a portion of water, and you can 
bend it in any direction. Much of the solid matter com- 
posing the body is gelatinous or glue-like, and has the 

1 Dr. H. Newell Martin : Human Body, pages 115-116. 



32 UNION SERIES, NO. 8. 

same power of soaking up water, without which it would 
become too hard to keep up the processes of life. Any- 
thing that interferes with the due amount of water in 
the tissues of the body impairs their power and impedes 
their action. 

(&) Water is a solvent for food. The whole process 
of digestion, as we shall see, consists in reducing food to 
a liquid form so that it can soak through the delicate 
membrane of the digestive canal into the blood-vessels. 
This could not be accomplished without water. 

(c) Water is a food-carrier in the body. Water makes 
up the greater part of the blood, and as the blood circu- 
lates it carries with it the dissolved food which soaks 
out of the blood-vessels upon the tissues. The tissues 
can then absorb the food much as a cloth can soak up 
sugar, salt, or coloring matter, when these are dissolved 
in water. If the food were not dissolved in water, the 
tissues could not soak it up any more than the cloth 
could soak up dry sugar or dry salt. 

(d) Water is also the carrier of waste. As we have 
seen, w r ater constitutes the greater part of the blood, 
which takes up and carries away from the tissues the 
worn-out particles that are no longer of use. 

3, Pure water is therefore the natural drink of human 
beings and the lower animals. No other liquid takes the 
same place. 

4. Water used for drinking always contains a small 
portion of mineral salts, of gases, and of vegetable mat- 
ter. Water which is absolutely pure — as only distilled 
water is — is flat and tasteless. The mineral elements in 
drinking waters are such as are not harmful to the sys- 
tem, unless there is too much of one kind, or too much 



PH YSIOL OGY AND HEAL TH. 3 3 

of all of them. In that case they are irritating to the 
bowels and kidneys. When water is carried through 
lead-pipes, it sometimes dissolves enough of the lead on 
its passage to become poisonous. Whether it will do 
that or not depends on what it already contains. Some 
waters may be carried through lead-pipes with perfect 
safety, either because the water does not act on the pipe 
at all, or because certain mineral matters which are in 
the water form a crust, lining the pipes and protecting 
them from further action. When lead-pipes are used, 
the question whether the water acts upon them should 
be settled by a chemist. Tin-pipes are safer. Water that 
is constantly running through lead-pipes is less likely to 
contain much lead than that w T hich stands still in the 
pipes for a long period. Lead, when taken in small quan- 
tities in this way, produces its bad effects very gradually, 
and health is often seriously affected before the cause is 
discovered. Among the symptoms of lead-poisoning are 
colic and paralysis of certain muscles. 

5. Offensive and poisonous substances, animal and 
vegetable, sometimes find their way into drinking water, 
and being dissolved in it, give no sign of their presence. 
Sewage and the germs of disease may thus be taken up. 
It is necessary therefore to guard the well or water-pipes 
very carefully from all impurities. Wells and reservoirs 
are often placed w T here they catch the drainage from 
barn-yards or other filthy places. Such drainage will 
go through the soil much farther than is commonly 
supposed. The fact that water is clear and sparkling 
and odorless does not prove that it is pure. A well 
or reservoir should not be located within thirty feet of 
any sloughy spot. Even at that distance it is not safe, if 



34 UNION SERIES, NO. 3. 

the ground is porous and slopes towards the well. In 
some cases aqueduct-pipes become leaky, and draw in 
filth. Constant watchfulness against such destroyers of 
health is necessary. 

Milk, Tea, and Coffee. 

6. Milk, our first food, is both a food and a drink. 
Of a hundred parts of milk about eighty-six parts are 
water. The remaining parts are food materials. 

7. People often attempt to improve water for a bev- 
erage, by steeping or infusing in it the leaves of the tea- 
plant or the berry or seed of the coffee-tree. Such drinks 
are called tea and coffee. It is probable that all persons 
would be in better health, if instead of drinking tea and 
coffee, they had always used water or milk — the drinks 
furnished by nature. Physicians who have studied the 
effects of tea and coffee agree that they injure children, 
and that young people are better without them. 

8. Cocoa is less injurious than tea or coffee. 

General Principles. 

9. While it is not necessary that all should adopt the 
same habits, there are certain principles which should 
govern all. The following are some of these, — 

(a) It is injurious to eat tempting food after the de- 
mands of a healthy appetite are satisfied. 

(b) It is important to eat at regular periods only. 
The stomach needs its regular times for rest. 

(c) All substances which simply please the palate, 
without furnishing any nutriment, — such as spices and 
other condiments, — should be used with caution. 

(d) Tobacco and alcohol are poisons, and both should 
be absolutely shunned. 



PHYSIOLOGY AND HEALTH. 35 

ILLUSTRATIONS. 

1. Illustrations of this chapter belong to the department of chem- 
istry chiefly. The teacher can enlarge on the subject by discussing 
many articles of food, and asking the pupil to classify them. 

2. To demonstrate, Section VIL, paragraph 3. Soak a piece of 
meat for twenty-four hours in alcohol, and note the effect. 



QUESTIONS. 

I 

1. What are Chemical Elements? How many are there? 

2, 3. How many chemical elements enter into the composition 
of the body? Name them. What elements compose our food? 

4, 5. Are any elements which do not enter into the composition 
of the body found in our foods ? 

6. Where are the elements which we require in our food to be 
found ? 

7. Can we take the elements that we need for nourishment 
wherever they are found? 

8. 9. How do plants differ from animals in their way of getting 
nourishment? What service do plants render to animals ? 

II 

1, What four elements are most abundant in the body of man? 
What proportion of the body do they form ? 

2, Which of the elements form the larger part of our food? 

3, Into what tw T o classes may food be divided? 

4, What subdivisions of food may be made? 

5, Name some nitrogenous and some non-nitrogenous articles of 
food. 

6, Eepeat or write on the board the classification of substances 
entering into food. 

7, Are these substances usually separate or mixed in our food 

stuffs ? 

in 

1. What is a carnivorous animal? an herbivorous animal? To 
which class does man belong? 

2-7. What can you say of milk as an article of food? of beef, 
veal, mutton, and pork? of fish? of eggs? of oysters? 



36 UNION SERIES, NO. S. 

8. 9. What is the most important class of vegetable foods? What 
is grain? Mention some of the different grains used as foods, and 
state the characteristics of each. 

10, 11, 12, 13. What can you say of peas and beans ? of the potato? 
of lettuce, celery, and small vegetables ? What class of substances 
predominates in animal food? in vegetable food? 

IV 

1, 2, Why is butter a useful article ? Why is sugar healthful ? 

v 
1, 2. Why do we cook our food? 
3, 4, What is the effect of bad cooking? 

5, Why is a knowledge of the art of cookery desirable? 

6, What is necessary in order to have good bread? 

7, 8, What do we mean by light bread? What is heavy bread? 

9. What makes bread sour? 

10. What caution is necessary in using pastry and cake? 

VI 

.1, 2. Do we eat mineral substances pure? Are such substances 
digested? 

3, 4, Should all observe the same habits of eating and drinking? 

5, 6. What besides appetite should guide us in the matter of 
eating and drinking? What is a sufficient daily ration for a man? 

VII 

1. Why cannot alcohol be classed with the nitrogenous foods ? 

2. How does alcohol affect muscular strength? 

3. How does alcohol interfere with the vital action of the tissues? 

4. 5. Mention points in which alcohol differs from food? 

VIII 

1. What is the proportion of water in the body? 

2. What four purposes does water serve in the body? 

3. 4, 5. What impurities may water contain ? Is water which is 
carried through lead-pipes always poisonous ? What are symp- 
toms of lead-poisoning? 

6, 7, 9. What kind of food is milk? What is the best course 
to pursue in regard to the use of tea and coffee? Name four 
principles which all should observe in eating and drinking. 



PHYSIOLOGY AND HEALTH. 37 



CHAPTER IV. 



ORIGIN AND NATURE OF ALCOHOL. 



All that Lives must Die. 

1. The bodies of plants and animals, as well as the 
human body, are composed of many elements, which are 
taken up into the system in the food these bodies absorb 
or imbibe. 

2. The plant receives its food from the ground by 
means of its roots, and from the air by means of its 
leaves. It grows to its full size, if it meets w T ith 
no hindrance, bears its seed, and when it has lived 
out its appointed time it dies. 

All that Dies must Decay or Go to Pieces. 

3. The next step in the order of nature after death 
is the decay or going to pieces of the animal, fruit, or 
plant. All the minerals, the gases, and other elements 
that were absorbed in plant, fruit, or animal, to build it 
up, must now be set free, in order that they may go to 
build up other living things. Otherwise the surface 
of the earth would soon be covered with dead trees, 
fruits, shrubs, grasses, and the bodies of dead animals. 
There would soon be no room for new growths, and 
perhaps no materials out of which new growths could 
be built. 



38 UNION SERIES, NO. 3. 

The Cause of Decay. 

4. If we leave cheese, bread, or any similar article 
of food in a damp place, we will soon find it covered 
over with mold. 

5. It was long ago noticed that fruit or other vege- 
table matter kept entirely away from the air would not 
decay, and hence the air was supposed to be the cause 
of the decay. The microscope has shown us that the 
decay is caused, not by the air itself, but by minute 
living things in the air belonging to the lowest forms 
of vegetable life. Among these are the molds and the 
ferments (which are closely related to the molds), each 
working upon different forms of matter and producing 
different kinds of decay. 

6. The germs of these molds and ferments, which 
correspond to the seeds of plants, float about in the air 
and are invisible to the naked eye. When they find a 
favorable soil, such as dead animal or vegetable matter, 
they enter it and begin to multiply rapidly, taking 
from it the substances which serve them for food. In 
doing so, they cause the animal or vegetable matter to 
decay or break up into the elements that compose it. 
Some of these go off into the air in the form of gas. 
All of them, sooner or later, as we have seen, enter into 
new matter often very different in its nature from that 
upon which the ferments began their work in the first 
place. 

How Alcohol is Produced by Ferments. 

7. Imagine that you hold in your hand a bunch of 
ripe grapes, just picked from the vines. Upon the sur- 



PHYSIOLOGY AND HEALTH. 39 

face of each grape is a thin coating of dust, called its 
"bloom," that can be rubbed off. This dust, if exam- 
ined with a microscope, will be found to contain germs 
of both molds and ferments. 1 

8. If the grapes are left to themselves the molds 
will, in time, cause them to decay or rot; but if the 
grapes are picked, and their juice is pressed out, this 
juice is caused to decay by the ferments. Ferments 
work only in the juice of fruit after it is pressed out. 
They are never found inside the fruit itself, 2 but easily 
wash off from the surface of the fruit into the expressed 

1 Pasteur, who is recognized as the greatest of investigators in 
this field, gives the following account of such an examination: 
"On September 27th we picked from a vine, in the neighborhood of 
Arbois, nine bunches of grapes, without injury to a single grape, 
brought them to our laboratory in a sheet of paper that had 
been previously scorched in the flame of a spirit lamp to destroy 
all germs that might adhere to the paper, and the grapes were 
cut off with a pair of fine scissors, which had also for the same 
purpose been passed through the flame. By means of a badger- 
hair brush, thoroughly purified in water, each grape to which 
a portion of its stem remained attached, was washed in a little 
pure water. The successive washing of a dozen grapes in a small 
amount of water was sufficient to make the water turbid ; we then 
examined it under the microscope, and saw many little organized 
bodies. As a rule the organisms consisted of simple, transparent, 
colorless cells; some, indeed, of larger size had a yellowish color, 
and were detached or united in irregular masses; and, lastly, 
there were club-shaped or bottle-shaped vessels, full of spores, 
ready to germinate." — Pasteur: Studies on Fermentation, page 152. 

By experimenting with these spores and germs, Pasteur proved 
that some of them were the germs of ferments. When placed in 
a sweet liquid, which had been previously purified from all other 
germs, they multiplied and produced alcohol. 

2 Pasteur: Studies on Fermentation, page 235. 



40 UNION SERIES, NO. 3. 

juice. Other ferment-germs floating in the dust of the 
air may fall into it. Ferments, like many other forms 
of life, could not live without oxygen. When they are 
resting on the stems or skins of the fruit, or are float- 
ing in the air, they obtain their oxygen from the air. 
When submerged in pressed-out fruit-juice, they take 
their oxygen from the sugar 1 of such juice. If this juice 
stands for a short time in a moderately warm place, 
bubbles of gas wall be seen rising through the liquid, 
and breaking into the air. 2 Each ferment is taking a 
small portion of oxygen from this sugar, and setting 

1 Most fruits contain some sugar, which forms in them while 
they are ripening. 

2 With a strong microscope the ferments themselves can be seen 
in the liquid. They are very small, transparent bodies, without 
head, legs, or other parts usual to plants or animals. The most 
remarkable thing about them is the rapidity with which they 
increase in numbers. From the side of one ferment a bud swells 
out, which, in about an hour, breaks off and forms a new ferment 
ready soon to send out new buds. 

Pasteur says, "On October 12th, at ten o'clock in the morning, 
we crushed some grapes, without filtering the juice that ran from 
them ; afterwards at different times during the day, we examined 
the juice under the microscope, until at last, although not be- 
fore seven o'clock in the evening, we detected a couple of cells. 
From that time we kept these cells constantly in view. At 7:10 
o'clock w T e saw them separate and remove to some little distance 
from each other. Between 7 and 7:30 we saw, on each of these 
cells a very minute bud originate and grow, little by little. By 
7:45 these buds had increased greatly in size. By 8 they had 
attained the size of the mother-cells. By 9 each couple had put 
forth a new bud. We did not follow the multiplication of cells 
any further, having seen that in the course of two hours two cells 
had furnished eight, including the two mother-cells. This increase 
would have been still more rapid at a higher temperature." 



PHYSIOLOGY AND HEALTH. 41 

the gas (carbonic-acid gas) free. As the sugar is thus 
broken up, a new substance, not at all like sugar, is 
formed and remains in the juice. This new substance 
is called alcohol, 1 and is a poison. Its presence makes 
the grape-juice, — which was healthful before the alcohol 
was formed, — a poisonous fluid, called wine. 

9. We have seen that the alcoholic ferments are not 
found within the fruit itself, hence there is no alcohol 
in fruits, grains, or vegetables, as they are prepared by 
nature for our use. 

10. The process by which healthful fruit-juices are 
turned into alcoholic liquors by the ferments is called 
vinous or alcoholic fermentation? There are several kinds 
of fermentation, but one law holds good for all, that is, 
fermentation entirely changes the nature of the substance it 
works upon. 

11. Before the nature of alcohol and its effects on the 



1 There are many alcohols, and all are the result of the fermen- 
tation of some organic substance, and all are poisons. Methyl 
alcohol is derived from fermented wood; Amyl alcohol, known as 
fusil oil, is derived from fermented potato-juice, etc. But the term 
alcohol, as ordinarily used, refers only to ethyl, or common alco- 
hol, derived from the fermentation of fruit-juices and certain other 
sweet liquids. 

2 Fermentation, in its widest sense, includes all forms of decay. 
But the term ferments is commonly restricted to alcoholic fer- 
ments. As used in this book the term has reference only to the 
alcoholic ferments. The botanical name of the genus to which 
alcoholic ferments belong is Saccharomyces. One species of these 
is found on all ripe garden fruits, and is called Saccharomyces 
apiculata. The species most abundant on the grape, and hence 
called the ferment of wine, is Saccharomyce r s ellipsoedius. The fer- 
ment of yeast is Saccharomyces cerevisix. 



42 UNION SERIES, NO. 3. 

human system were as well understood as now, people 
thought that alcohol was a food that would in some way 

aid health and lengthen life. 

^ ^ % \ I 1 n During the past few years, how- 

i/ i/ ^ ^ ever, this treacherous liquid has 

been more carefully studied than 
ever before, and those who now best understand its nature 
and effects unhesitatingly class it as a poison that injures 
health and shortens human life. 

II 

Alcohol a Narcotic Poison. 

1. A poison is any substance whose nature it is when 
absorbed into the blood to injure health and destroy life. 

2. Poisons that stupefy, deaden or paralyze the brain 
are called narcotic poisons. Alcohol is a narcotic poison, 
because it deadens or paralyzes the brain and nerves 
according to the amount taken. 

Alcoholic Appetite. 

3. There are many different classes of poisons, some 
exerting their injurious and destructive effects upon one 
part of the body in one way, and some injuring other 
parts in a different way. We have seen that alcohol ' is 
a narcotic poison. Narcotic poisons have the power to 
create an ever-increasing appetite for themselves. Alco- 
hol has this power in a marked degree, and in whatever 
form or quantity taken. The character of a substance 
does not depend upon its quantity, but its quality. In 
whatever liquors alcohol is found, whether in those that 



PH YSIOLOG Y AND HE A L TH. 43 

contain much of it, as brandy and rum, or little, as 
beer, wine, and cider, its character is always the same. 

4. When water comes into contact with living tissues 
they absorb it, and are satisfied. Water is a natural 
drink and quenches natural thirst. When alcohol is 
brought into contact with living tissues, it irritates them 
and creates thirst. For this unnatural thirst there is 
no natural limit, 1 If more alcohol is taken, it has the 
power to still further increase the disturbance and rouses 
a still more imperious demand, that is never satisfied, 
even when the drinker's arm is paralyzed and he can no 
longer lift his glass. Even then, in his drunken mutter- 
ings, he calls for more, and his first thought on regaining 
consciousness is again — more. 

5. Those who witness the ruin alcohol brings to the 
drunkard are apt to charge his degradation to his weak- 
ness in " drinking too much ; " but any is " too much," 
because it is the nature of a little alcohol to create an appetite 
for more. Thus, there is a logical and scientific connection 
between the first glass and the drunkard's fate. It is not 
the weakness of the drinker, but the nature of the drink 
that causes drunkenness. 2 

1 " Only natural appetites have natural limits. The art of the 
pastry cook would hardly induce his customers to stupefy and 
beastialize themselves with his compounds. There are no milk- 
topers, no suicidal potato-eaters, no victims of a chronic porridge 
passion." — Felix Oswald, M. D. : The Poison Problem. 

2 " People sometimes wonder," says Dr. Jennings, " why such 
and such men, possessing great intellectual power and firmness of 
character in other respects, cannot drink moderately and not give 
themselves up to drunkenness. They become drunkards by law 
— fixed, immutable law. Let a man with a constitution as perfect 
as Adam's undertake to drink alcohol, moderately and persever- 



44 UNION SERIES, NO. 3. 

6. The rapidity with which the craving for alcohol 
grows upon its victim varies with the individual. Every 
person who drinks a glass of wine may not become a 
drunkard, but no one who drinks alcoholic liquors, even 
in small quantities, can tell how soon they may create in 
him the imperative appetite, which, resisted, is torture; 
yielded to, is ruin. Entire abstinence is the only sure 
preventive against forming the alcoholic appetite, — and 
the only remedy when such an appetite is formed. Even 
so small a quantity of alcohol as that in the wine often 
used to flavor jellies, puddings, sauces, etc., is capable of 
rousing a slumbering appetite that may have been for 
a long time repressed. Alcoholic liquors in any form 
should never be used either as a beverage or as a flavor- 
ing for food. 

7. Because people have not understood the origin 
and nature of alcoholic drinks, they have supposed the 
"lighter liquors/' such as beer, wine, and cider, to be 
harmless. But we have seen the power a little alcohol 
has to create an appetite for more. This makes any 
liquor containing it a treacherous as well as a seductive 
drink. 

ingly, with all the caution and deliberate determination that he 
can command, and if he could live long enough he would just as 
certainly become a drunkard, — get to a point where he could not 
refrain from drinking to excess, — as he would go over JSIagara 
Falls when placed in a canoe in the river above the falls and left 
to the natural operation of the current. And proportionately as 
he descended the stream would his appetite for alcohol increase, 
so that he would find it more and more, difficult to get ashore, 
until he reached a point where escape was impossible.'' — Medical 
Reform, page 175. 



PH YSIOLOG Y AND HE A L TH. 45 



Cider. 

8. Perhaps none of the alcoholic beverages has started 
more people on the road to drunkenness in this country 
than cider. 

9. As in the case of grapes, ferments, too small to be 
seen by the naked eye, rest upon the skins and stems 
of apples from which cider is made. When the apples 
are ground, and the juice is pressed out, some of these 
ferments are easily washed off into the liquid. If it is 
moderately warm, they begin at once to break up the 
sugar of the juice into carbonic-acid gas and alcohol. 
The gas passes out of the cider in bubbles; but the 
alcohol remains in it, and whoever drinks the cider gets 
some of this poison. The ferments multiply so rapidly 
that alcohol can usually be found in cider within six 
hours after it is pressed out. From this time on, the 
amount of alcohol in the cider gradually increases as 
the ferments continue their work, and the cider is said 
to be growing hard. Often one part in ten of hard 
cider is alcohol. One peculiar fact about cider-drink- 
ing is, that it tends to make those who drink it ill- 
tempered. 1 

10. When cider, beer, or wine, or a similar fermented 
liquor, is left open to warm air, another form of fermen- 
tation takes place, which produces vinegar. This is done 
by a ferment, known as the mother of vinegar, which 
grows upon the surface of all such liquids, and produces 

1 " The form in which alcohol is taken determines in some 
degree the character of the mental state it produces. Cider makes 
the ugliest drunkards." — E. Chenery, M. D.: Facts for the Millions. 



46 UNION SERIES, NO. 3. 

a fermentation, called acetous fermentation. In acetous 
fermentation, the alcohol of the wine, or cider, or other 
similar liquor, is changed to a sharp acid. You remem- 
ber the law that fermentation changes the nature of 
the substance that it works upon. Vinous fermentation 
changes the healthful sugar of sw r eet liquids to alcohol, 
which is a poison. Acetous fermentation changes the 
poison, alcohol, to a sharp acid, totally unlike alcohol 
in its nature, that may be safely used to flavor food. 
There is no alcohol in vinegar. 

Beer. 

11 . Beer is one of the so-called " lighter liquors," and 
was at one time thought to be a harmless drink. But 
experience and science have both shown it to be far 
from harmless. It is the product of alcoholic fermen- 
tation, and, like other fermented liquors, is poisonous, 
because of the alcohol contained in it. 

12. Beer is usually made from barley, sometimes from 
other grains. As grain has no sweet liquid necessary 
for fermentation, this is produced by first sprouting the 
grain, which turns its starch into sugar ; second, heating 
the grain to stop further sprouting; third, mashing or 
grinding it; fourth, soaking out its sugar with water; 
fifth, adding yeast to produce alcoholic fermentation. 
Yeast is one kind of ferment. Hops give the beer its bit- 
ter flavor. The yeast sets up fermentation, by breaking 
up the sugar into the carbonic-acid gas which bubbles 
out of the liquid into the air, and to alcohol, wdiich 
remains in the beer, making it poisonous. 

13. Like all poison habits, the habit of beer-drink- 
ing is progressive. Beer has the pow T er of creating an 



PHYSIOLOGY AND HEALTH. 47 

appetite that requires an immense amount of beer or 
of stronger liquors for its gratification, while it brutalizes 
and stupefies the drinker in proportion to the amount he 
imbibes. Beer has been well called " one of the most 
annualizing of drinks." It obscures the intellectual and 
moral faculties, while it also arouses the worst passions 
of human nature. Beyond all other drinks it qualifies 
for deliberate crime. 

Ill 

Distillation and Distilled Liquors. 

1. The largest amount of alcohol that can be produced 
in any liquid by fermentation is about seventeen parts 
in one hundred. More than this stops the work of the 
ferments. But men have invented ways of obtaining 
liquors much stronger with alcohol, and almost pure 
alcohol itself. Their ability to do this depends upon 
the fact that alcohol may be turned into vapor at a 
much lower temperature than water. It may there- 
fore be separated from the water in such liquors as 
wine or cider by heating them. This is done in a cov- 
ered vessel with a pipe in a close-fitting cover. As the 
alcohol rises in vapor, it passes through the pipe which 
is cooled with ice. The alcoholic vapor condenses to a 
liquid which is much stronger with alcohol than the 
liquid put into the covered vessel, and is collected as it 
drops from the end of the pipe. This process is called 
distillation. The alcoholic liquors obtained by distilla- 
tion are brandy, rum, whisky, and gin. 

2. Distilled liquors are commonly about one-half 
alcohol, and therefore have great power to harm the 
human system, and quickly ruin those who drink them. 



48 UNION SERIES, NO. 3. 

By swallowing more in quantity, the beer, wine and 
cider drinker often gets as much alcohol as the drinker 
of distilled liquors. 1 The use of the lighter wines, so- 
called, is a prolific cause of intemperance, for it is the 
nature of the alcohol in these, as well as in all other 
alcoholic beverages, to make the drinker want more. In 
countries where light wines and beer are most used, more 
of the stronger liquors are also used, and intemperance 
rapidly increases. 

"Our impression is that the lowest, slowest, and most illiterate, 
most unimpressible, most unimprovable, if not vicious population 
outside of the great cities, is found in the oldest wine districts, 
and that the use of the product of vineyards has been the most 
active cause of this condition of the population; that the in- 
creased production and consumption of wine on this coast in 
the most recent years has diminished the use of neither distilled 
liquor nor lager-beer, but rather increased the demand for both. 
We never hear of people who forsake liquor and beer for the sake 
of wine, but we hear of many who never use an intoxicant till 
they learn to love wine, and then have abandoned wine for some- 
thing stronger. In a word, we do not believe that wines reform 
anybody, and we do believe that they beguile many into drinking 
habits, and finally into drunkenness, who would never have drank 
a drop but for wine." — Editor of The Pacific. 

1 " All poison habits are progressive. The beer vice is always 
apt to eventuate in a brandy vice, or else to equalize the differ- 
ence by a progressive enlargement of the dose of beer." — Felix 
Oswald, M. D. : Poison Habit, page 55. 



ILLUSTRATIONS, 

1. Examine with a microscope having a magnifying power of 
at least four hundred diameters, mold from cheese, or other 
substance, or yeast. 



PHYSIOLOGY AND HEALTH. 49 



QUESTIONS. 



I, 2, 3. State the law of death and decay. 
4, 5. What is the cause of decay? 

6. How do molds and ferments bring about the decay of a 
substance ? 

7. Give Pasteur's account of finding mold and ferment germs 
on grapes. 

8. How does mold affect grapes ? What part of the grapes do 
the ferments attack? Do they attack the juice while it is in the 
whole fruit? What must the ferments have in order to live? W^here 
do they get this oxygen when they are submerged in the expressed 
grape-juice? What is the result of the breaking up of the sugar 
by the ferments? 

9. Why is there no alcohol in fruit as it grows for our use? 

10. What is vinous fermentation ? State the law of fermentation. 

II. Is alcohol a food or a poison? 

II 

1. Define a poison. 

2. What is a narcotic poison? 

3.^ What kind of an appetite has alcohol the power of creating? 

4. What effect has water upon thirst? What is the relation of 
alcohol to thirst? What is the difference between a natural thirst 
and the thirst created by an alcoholic liquor? What has every 
additional quantity of alcohol taken the power to do? 

5. What fact shows the connection between the first glass and 
the drunkard's fate? To what is the drunkard's condition often 
charged? Is it the weakness of the drinker, or the nature of the 
drink that leads to drunkenness? 

6. What can you say of the rapidity with which the craving for 
alcohol grows upon its victim? What is the only sure preventive 
against forming the alcoholic appetite? W T hat is the only remedy 
for such an appetite when formed? What is the danger in using 
alcoholic liquors for flavoring food? 

7. W T hy is it a mistake to think the use of the lighter liquors 
harmless ? 



50 UNION SERIES, NO. 3. 

8. What can you say of cider drinking in this country ? 

9, How does cider become alcoholic? How long after cider is 
pressed does alcohol begin to appear in it ? What is the propor- 
tion of alcohol in hard cider ? How does the use of hard cider 
often affect the disposition? 

10, How is hard cider changed to vinegar? Why is there no 
alcohol in vinegar ? Show how the law of fermentation is carried 
out in vinous and acetous fermentation? 

11. What have science and experience shown concerning the 
nature of beer ? Why is it poisonous ? 

12, Describe the process that leads to the formation of alcohol 
in beer? 

13. What has beer the power of causing? What are some of 
the effects beer is likely to have upon the drinker? 

hi 

1. What proportion of alcohol can be produced in a liquid by 
fermentation? Are any drinks stronger with alcohol than this? 
How are they made? 

2, What proportion of alcohol do distilled liquors contain? 
May lighter liquors be as injurious as the stronger? 



PHYSIOLOGY AND HEALTH. 51 



CHAPTER V. 



DIGESTION. 



1. One thing that distinguishes living things from 
dead matter is that all living things have the power of 
taking substances into themselves, and making them 
a part of themselves. That is what we do w T hen we eat 
and drink. 

2. Dead substances may take to themselves new mat- 
ter and grow in size. The icicle hanging from the eaves 
does this, and the snow-ball started down a hill-side. A 
stone may grow by the deposit of material on its surface. 

3. But it is easily seen that this kind of growth is 
very different from that of living things. This kind of 
growth is called growth by "accretion/' — adding to itself 
a substance like itself. Living things grow by " assimila- 
tion," — taking into themselves substances different from 
themselves and making them a part of themselves. 

4. Substances are taken into the body through the 
mouth and nose. Through the nose we take in air only. 
Through the mouth we take in many different substances, 
some of them in the solid and some in the liquid state, 
which we call food and drink. 

5. The process of taking in air through the nose or 
mouth will be treated in another place. In this chapter 
we will study the parts of the body by which food and 



52 



UNION SERIES, NO. 3. 



drink are received, and the changes which are made in 
food and drink before they are taken into the blood. 

The Alimentary Canal. 

6. The parts which receive and act thus upon food and 

drink are designated as 
the " Alimentary Canal 
and its Appendages." 

7. The alimentary 
canal is a long tube 
which begins at the 
lips, and has its outlet 
at the lower end of the 
trunk. The appendages 
to the alimentary canal 
are the salivary glands, 
the liver, and the pan- 
creas. 

8. The length of the 
alimentary canal in 
man is about twenty- 
seven feet (8.2 m -). In a 
sheep it is eighty or 
ninety feet (24 m - to 27 m *). 
Such a long tube must 
necessarily be coiled up, 
as it is in that part of 
it which constitutes the 
intestines or bowels. 

9. This tube is con- 
tinuous from beginning 
to end, but different 

parts of it have different names. The main divisions 




PHYSIOLOGY AND HEALTH. 



53 



are obvious and natural, but certain subdivisions are 

made which are artificial, — for example, the duodenum 

in the small intestine. The following table indicates its 
divisions : — 



The Mouth. 
The Throat. 
The Gullet. 



The Stomach. 

The Small Intestine. 

The Large Intestine. 



10. The alimentary canal is not of the same diameter 
throughout. The stomach is a pouch four or five inches 
(10 to 13 c - m> ) wide. The canal widens here, just as a river 
in its course sometimes widens into a lake. The small 
intestine is not more than one inch or one inch and a 
half wide. The large intestine is twice as wide as the 
small intestine. 

11. The walls of the alimentary canal are thin and 
flexible. They are made in part of muscle-fibers which 
run lengthwise and cross- 
wise around the tube. It is 
by the working of these mus- 
cle-fibers, first shortening and 
then lengthening, that food 
is churned and kneaded and 
forced along down. 

12. The canal has a soft, 
moist, smooth lining, called 
the mucous membrane. In 
the lining are innumerable pores which open into little 
pits, called glands. These glands make the juices, called 
digestive juices, which mix with the food and digest it. 
This is a description of the canal as a whole. Now 
examine each of its divisions. 




54 



UNION SERIES, NO. 3. 



The Mouth. 

13. The lips are the outer gates and the teeth are the 
strong inner gates through which the mouth is entered. 
The teeth begin the work of dividing up and preparing 
the food for digestion. 

An infant has at first no teeth visible, though there 
are some buried in the gums and ready to come out at 

the right time. 
2 /^C^^3 ik a At five or six 

months' old the 
front teeth ap- 
pear and are fol- 
lowed by others 
at intervals of a 
month or two. 
At from two to 
two and a half 
years all of the 
They are twenty in 




year 
Molar 



first set should have appeared, 
number as follows: 



Incisors, or cutting teeth . 
Canines, or long-pointed teeth 
Molars, or grinders, 



Total 20 

.14. At from five to seven years of age, the front teeth 
(the incisors) loosen and come out and the other teeth fol- 
low one by one, and all are succeeded by the teeth of the 
second set. The time at which they will appear cannot 
be precisely stated. Most of the second set have come 
by fourteen years of age. But there are still four wisdom 
teeth which do not appear before seventeen years of age, 
and often not until much later in life. 



PHYSIOLOGY AND HEALTH. 55 

15. The second set consists of thirty -two teeth, which 
do not exactly correspond to those of the first set. They 

are, — 

Incisors 8 

Canines 4 

Bicuspids ...... 8 

Molars 12 

Total ...... 32 

16. The incisor teeth and the canines are adapted to 
cutting and tearing food. The bicuspids and molars 
are adapted to grinding it. 

17. The teeth are not bones, though they are very 
much like bone. They differ from bone as ivory differs 
from bone. A tooth may be divided into three parts — 
the crown, the neck, and the root. The root may have 
a number of fangs. The teeth have a cavity in the cen- 
ter which contains the pulp. In the pulp lie the nerve 
and blood-vessels, which enter by a small hole in the 
end of the fang. The crown is covered by a thin layer 
of enamel, which is the hardest substance in the body. 

Care of the Teeth. 

18. The teeth cut and grind the food and mix it 
with the saliva. It is very important that this should 
be thoroughly done. Otherwise the food cannot be well 
digested. Accordingly, the teeth should be protected 
and cared for. They may be injured by hot or cold 
substances ; by some medicines ; by decomposing food 
remaining in them ; by tobacco. They should be thor- 
oughly brushed at least once a day. They should be 
examined occasionally by a dentist, and if they are begin- 
ning to decay they should be filled. In this w^ay even 
imperfect teeth may be preserved for a long time. 



56 



UNION SERIES, NO. 3. 



19. If the teeth are neglected, the mouth will be filled 
before youth has passed with decaying stumps, which are 
a source of pain and mortification, and which often poi- 
son the blood and impair the health. Such teeth should 
be removed at once. Fortunately, the dentist can give us 
something better. 

The Tongue. 

20. The tongue has two offices: First, in articulation; 
second, in moving the food. It is itself made of muscle, 
the fibers of which run longitudinally, transversely, and 
vertically. It is also acted upon by muscles descending 
from above, ascending from below, extending from the 
lower jaw-bone backward, and from behind forward. It 
is capable, therefore, of changing its shape, and of mov- 
ing with great rapidity and precision in every direction. 

Both in articulation and masti- 
cation, it has very delicate work 
to do. It is aided in this by a 
most delicate sense of touch. In 
no other part is this sense so 
fine and accurate. The tongue 
shifts and turns the mass of food, 
placing it deftly between the 
teeth, and finally passes it back 
to the throat. 

The Throat.— The Gullet. 

21. The throat is a portion of 
the alimentary canal, about four 
inches (10 c - m ) long. Both the nose and the mouth open 
into it. The windpipe and the gullet lead out of it below. 




PHYSIOLOGY AND HEALTH. 57 

22. The gullet lies just behind the windpipe, and is 

nine inches (22.8 c - m -) long. It opens into the stomach. 

Its walls are soft, and are always pressed close together, 

except when something is passing down. The lower end 

of the gullet is nearly opposite the lower end of the 

breast-bone. 

The Stomach. 

23 . The stomach is a pouch about a foot (30 c - m -) long, 
which lies under the heart, separated from it by the 
diaphragm. The diaphragm is a thin membrane, and 
when the stomach is swollen w 7 ith gas, as happens in 
the case of indigestion, it presses the diaphragm up, and 
crowds the heart. This causes uncomfortable and some- 
times distressing sensations in the heart. A fancied 
heart disease is often only dyspepsia. 

24. In an infant the stomach lies almost in the direc- 
tion of the backbone, — up and down. It is very easy 
for an infant to throw up the contents of the stomach. 
In a grown person the stomach lies more nearly across 
the backbone. It is joined to the gullet, as the foot is 
joined to the leg, nearly at a right angle. Therefore it 
is more difficult for a grown person to vomit. 

25. Like the rest of the alimentary canal, the stomach 
has muscle-fibers in its wall. These muscle-fibers are 
in three layers, which run in different directions. One 
layer surrounds the stomach, another layer runs length- 
wise. Another runs in an oblique direction. By the 
contraction of these layers, the stomach can squeeze and 
knead its contents thoroughly. 

26. The lining of the stomach is pinkish in color, 
and has in it innumerable pores opening into the little 
pits, called glands, already referred to. These glands 



58 UNION SERIES, NO. 3. 

manufacture the gastric juice. Some of them are single 
tubes and others are branched. 

The Pylorus. 

27. At the lower end of the stomach the small intes- 
tine begins. At this point there is a ring of muscle 
surrounding the tube which can keep it closed. This 
ring is called the pylorus, which means the " keeper of 
the gate." Its duty is to let no food pass down which 
is not properly mixed with the saliva and gastric juice. 
It is a very obstinate gate-keeper, and sometimes holds 
undigested matter in the stomach for twenty-four hours 
or more until it is finally thrown up. Sometimes the 
keeper gets tired of resisting, and the offending sub- 
stances pass down, causing perhaps pain in the bowels. 
The small intestine is twenty feet (6 m -) long, and the 
large intestine, which is the lower part of the alimen- 
tary canal, is five feet (1.5 m ) long. The upper part of 
the small intestine for about ten inches (25 c,m ) is called 
the duodenum. Here an important part of the work 
of digestion is done. In the lining of the intestines, 
small and large, are found millions of pores similar to 
those in the stomach. They also manufacture a fluid 
which aids digestion. 

II 

The Salivary Glands. 

1. Before describing the salivary glands, it will be 
well to define a gland. There are many organs of the 
body which we call glands. The liver and spleen and 
kidneys are glands. The little pits in the lining of the 
stomach, just described, are glands. We have sweat- 



PHYSIOLOGY AND HEALTH. 



59 



glands in the skin and tear-glands in the eye. These 
differ in structure and size and appearance very much. 
In one thing they are all alike. All except the spleen 
have for their work to manufacture some fluid to be 
used in the body, or to be thrown out of the body. ' The 
spleen and a few other glands have for their work to 
make some changes in the blood and lymph. We can 
say, therefore, that a gland is an organ w T hose work it is 
to manufacture or modify the fluids of the body. 




2. The salivary glands manufacture saliva. There 
are three pairs of them. 

(a) The parotid ^glands. These lie under the ear. In 
mumps they swell and are painful. Their outlet is a 
tube two and a half inches (6 cm -) long, which runs straight 
forward in the cheek, and opens into the mouth oppo- 
site the second molar tooth. 

(b) The submaxillary glands. These lie just under the 
floor of the mouth, inside the jaw-bone. Their outlet 



60 



UNION SERIES, NO. S. 



is under the tongue close to the middle line. The fluid 
can sometimes be seen to spurt from them. 

(c) The sublingual glands. These are the smallest of 
the three pairs, and lie farthest forward. They are 
beneath the floor of the mouth, and pour their fluid into 
it by several small openings. 

3. The salivary glands are called compound glands. 
They each consist of a great many tubes, with little sacs 
on the ends of them, like grapes on a stem. These little 
tubes empty out into larger tubes, until finally all are 
joined in one large tube, which is like the main stem of a 

bunch of grapes. Blood-vessels 
pass between the tubes and 
surround the sacs. The saliva 
is made in the sacs from the 
blood, and flows out through 
the tubes. 

4. The saliva is a mixed 
fluid from the three pairs of 
glands. The fluid from the 
parotid glands is thin and 
watery. That of the other 
glands is thicker, and makes 
a slippery coating over the 
food in the mouth. 

The Liver. — Gall Bladder. 

5. The liver is the largest 
gland in the body. It weighs 

about four pounds, and lies behind the lower ribs on 
the right side, and extending over the pit of the stomach 
in front to the left side. 




PHYSIOLOGY AND HEALTH. 61 

6. The gall-bladder is closely connected with the under 
surface of the liver. It is a sac about three inches (8 c,m> ) 
long, shaped like a slender pear. The duct of the liver 
is a tube about as large as a goose-quill, which opens 
into the upper part of the small intestines. The duct of 
the gall-bladder joins the duct of the liver. The gall- 
bladder is a receptacle for bile, when it is not needed 
in the intestines. 

7. We infer from the size of the liver that it must 
do a very important work. It makes almost a quart of 
bile daily. Bile is a yellow fluid which becomes green 
if it remains in the stomach or bowels long. It has a 
very bad taste. It helps to digest food. 

8. Sometimes the duct of the liver becomes stopped. 
Then the bile as it forms in the liver is prevented from 
flowing out. The blood-vessels take it up, and carry it 
all through the sj r stem. It is deposited in the tissues, 
and gives the skin the yellow color which is seen in 
jaundice. The bile which is thus retained is a poison 
to the whole system. The liver in making bile purifies 
the blood. 

9. The liver also makes and stores up glycogen. This 
is a substance like starch in its chemical composition. 
It is made chiefly from the sugars and starches in our 
food. Vegetables make and lay up a great deal of starch. 
Animals make very little. The most of what animals 
make is stored up in the liver as glycogen. 

The Pancreas. 

10. The pancreas, the sweet-bread in calves, is a long, 
slender gland which lies behind the stomach across the 
backbone. It is a good deal like the salivary glands 



62 



UNION SERIES, NO. S. 



in its construction. It is a compound gland, made up 
of numerous small sacs and tubes uniting until they 
form one large tube or duct, which empties into the 

upper part of 
the small in- 
testines at the 
same opening 
which admits 
the bile. The 
pancreas, al- 
though one of 
the smallest 
glands, makes daily a pint and three-quarters (800 s rms - ) of 
a very active fluid, the pancreatic juice. It does a con- 
siderable part of the work of digestion. 




Ill 

Digestion. 

1. The alimentary canal corresponds to the kitchen 
in a hotel, where food is received from the street, and is 
prepared before it is distributed to the various rooms as 
it is demanded. So before the food can become part of 
the blood, and be carried to the hungry tissues, it must 
undergo a change. That alteration takes place in the 
alimentary canal, and is called digestion. 

2. The food is acted upon in two waj r s in digestion. 
(1) Mechanically, by the cutting and grinding of the teeth 
and by the kneading of the stomach and intestines. (2) 
Chemically, by the action of the digestive fluids. 

3. In the mouth food is cut and ground into bits, 
and is thoroughly mixed with saliva. This prepares it 



PHYSIOLOGY AND HEALTH. 63 

to be acted on by the juices of the stomach. Food which 
is swallowed in lumps is slowly and with difficulty 
penetrated by the gastric juice. Hence the great impor- 
tance of eating slowly, and thoroughly masticating the 
food. 

4. The saliva, besides softening portions of the food, 
and covering them with a slippery coat, which makes it 
easy to swallow them, also acts directly on the starchy 
substances, changing them into sugar. Starch cannot 
pass through the wall of the alimentary canal, even 
should it be dissolved. Sugar can. Hence all starchy 
matters are changed into sugar, and this change is begun 
by the saliva. 

5. The average amount of saliva which gets into the 
mouth in twenty-four hours is at least a pint and a half. 
(.8 L.) It flows freely when we are eating. Even the 
thought of food causes the mouth to water. When we 
are not eating, it serves to keep the mouth moist, and 
so makes articulation possible. Fear sometimes stops the 
action of the salivary glands, and so the young orator, 
it may be, finds his " tongue cleaving to the roof of his 
mouth " when he makes a speech. 

6 . The soft and smooth mass of food is pressed back 
by the tongue into the throat, and the muscles there 
contract around it in such a way as to send it into the 
gullet, and the gullet, contracting above it, forces it into 
the stomach, as w^e might strip fluid out of a flexible 
tube by drawing it between our finger and thumb. 

7. When the mouthful of food arrives in the stomach, 
the lining of that organ is flushed by the blood flow- 
ing into it, and the little glands begin to pour out the 
gastric juice. It stands in drops at the mouths of these 



64 UNION SERIES, NO. 3. 

glands, as perspiration stands on the surface of the skin. 
The drops succeed each other rapidly as more food is 
introduced. 

8. We will suppose that the mouthful of food con- 
sists of meat, bread, and butter. Of these only the meat 
and a small portion of the bread are really digested in 
the stomach. The butter is scarcely changed. The 
meat is liquified, and made into a substance called 
peptone, which can easily pass through the walls of the 
alimentary canal, as pure meat juice cannot. 

9. If the gastric juice is not sufficient in quantity, or 
if it is poor in quality, digestion does not go on well 
and distress may result. 

10. After food has remained in the stomach a vary- 
ing length of time- — for some substances half an hour, 
for others several hours — that which is not fully digested 
passes into the duodenum. It has become a thick liquid 
like gruel, gray in color, and is called chyme. 

11." In the duodenum the chyme meets the bile and 
the pancreatic juice. The starchy matters, represented in 
this case by bread, were acted on a little by the saliva, 
but not at all by the gastric juice. The pancreatic juice 
mixes with them and digests them, by changing them 
to sugar. The fat represented by butter has not been 
changed in the stomach. The bile and the pancreatic 
juice digest that by making an emulsion of it. 

12. An emulsion is a thorough mixture of fat or 
oil with some fluid. We cannot make an emulsion with 
pure water. The oil may be mixed for a moment, but it 
will soon rise to the top, while the water settles below 
it. But the pancreatic juice makes a perfect emulsion. 
The oil stays mixed, and its particles are very finely 



PHYSIOLOGY AND HEALTH. 65 

divided. When oil is in this condition, it is capable of 
passing through the walls of the alimentary canal. 

13. Meat and other animal foods are digested chiefly 
in the stomach. Bread and other starchy foods and the 
fats are digested chieflv in the duodenum. The little 
glands in the wall of the intestine below the duodenum 
give out a fluid called the intestinal juice. This aids in 
completing the process of digestion, and keeps the mass 
of food moist. 

14, There is always some portion of our food that 
is indigestible, — the woody parts of vegetables and the 
gristle in meats, for example. Such substances pass 
through the alimentary canal without essential change. 

IV 

Effects of Alcohol. 

1. If a few drops of clear alcohol are taken into the 
mouth, they make a burning sensation. A little larger 
quantity gives pain. We reject it at once, as we would 
corrosive acids or other substances capable of injuring 
the mucous membrane. 

2. Alcohol is a chemical agent of great power. When 
brought into contact with animal tissues, it extracts the 
water which they contain and coagulates the albumen. 
In the living tissue, by its irritant action, it produces 
important changes. 

3. The pepsin of the gastric juice is precipitated by 
alcohol, so that fluid loses its digestive power as long as 
the alcohol remains in the stomach. 

4. These facts can be shown by experiment in the 
laboratory, and have been confirmed by observation of 
human subjects. 



66 UNION SERIES, NO. 8. 

5. Dr. Beaumont, in those studies of the stomach 
of Saint-Martin, which gave us much of our present 
knowledge of that organ, made careful and repeated ob- 
servations of the effect of alcohol upon it. 1 He discovered 
that after the frequent use of alcoholic drinks for several 
days, the lining of the stomach looked inflamed ; patches 
of ulceration appeared ; the gastric juice became ropy 
and tinged with blood. The ulceration and change in 
the secretion increased as he continued the use of spirits. 
"But," says Dr. Beaumont, "these morbid changes are 
seldom indicated by any ordinary symptoms or particular 
sensations complained of, unless when in considerable ex- 
cess." Much damage may be done to the stomach while 
the drinker is unaware of it. 

6. Alcohol hinders digestion in still another way. 
Through its power of extracting water, it is capable of 
hardening the food that should be dissolved in the 
stomach, and thus renders it less easy of digestion. 

7. The erroneous belief that wine, beer, or cider, aids 
digestion has often led to the formation of the alcoholic 
appetite, and to injury of the stomach that has resulted 
in dyspepsia. 

8. It is the belief of physicians that dyspepsia is a 
common result of indulgence in alcoholic beverages. 2 

1 Saint-Martin was a French-Canadian, who had an opening 
through his side into his stomach, in consequence of a gunshot 
wound. Dr. Beaumont took the man into his service, and for 
eight years made studies, at different times, of the inside of the 
stomach and the processes going on there. 

2 Dr. B. W. Richardson says, that it is one of the most definite 
of facts, that persons who indulge even in what is called the 
moderate use of alcohol suffer often from dyspepsia from this 
cause alone. 



PHYSIOLOGY AND HEALTH. 67 

9. The train of effects in the stomach, caused by the 
use of alcoholic liquors, is congestion, ulceration, thicken- 
ing and ultimately contraction of the mucous membrane, 
with the obliteration of many of the glands which supply 
the digestive juice. 

10. But while digestion and the stomach itself are be- 
ing ruined by strong drink, they are becoming more and 
more dependent upon it. The want of appetite for food 
and the gnawing or burning at the pit of the stomach 
are intolerable. The drinker craves more alcohol. This 
gives a temporary relief, but increases the trouble. 

11. The effect of alcohol on the intestines is less com- 
monly observed than its effect on the stomach. For 
much of it passes out before reaching the lower part 
of the alimentary canal. But it is similar. The same 
irritant action produces the same congestion, and the 
same permanent changes in the lining membranes. 

12. From the stomach alcohol is carried in the blood 
directly to the liver, where it filters through the liver- 
tissues and is the cause of injurious changes. It leads 
to an excessive overgrowth of connective tissue between 
the liver-cells and surrounding the blood-vessels. This 
new growth of connective tissue gradually contracts, and 
crowds the blood-vessels within it, hindering the natural 
flow of blood, and also compresses the enclosed liver 
substance. The cells, thus compressed, shrink, and cause 
the liver to contract in places, leaving little projecting 
knobs in other spots where the cells are not yet injured. 
Such a liver is sometimes called a " hob-nailed liver " 
from its appearance, or "gin-drinker's liver" from its 
w^ell-known cause. This condition of the liver inter- 
feres with the proper preparation of bile and other work 



68 UNION SERIES, NO. 3. 

of the liver essential to health, and is not brought about 
by hard drinking only, but may be caused by the con- 
tinuous excitement kept up by habitual " tippling." 1 



Hygiene of Digestion. 

1. Good digestion is one of the chief foundations of 
our health, and an important condition of happiness. 
Unless the work of the alimentary canal is properly 
done neither body nor mind can work well. Dyspepsia 
means bad digestion. It is often caused by not taking 
proper care of the stomach. Some people have by 
nature strong stomachs, which will bear much neglect 
and ill-usage. Others have weak stomachs, and these 
must be treated w T ell. 

2. To maintain good digestion several rules should 
be observed, — 

(a) We should not eat fast. We cannot chew our 
food properly if w T e do, and the lumps w T hich pass into 
the stomach are not easily digested by it. 

(b) We should not eat too much. If the stomach is 
too full it cannot knead the food, and the digestive juices 
may not be sufficient for the mass. That part which 
is not digested will decompose, producing acidity and a 
pressure of gas. 

(c) Fried food is indigestible, because the fat which 
is cooked into it coats over the particles, and protects 
them against the action of the digestive juices. 

(d) Great fatigue or great excitement hinder digestion. 

1 Dr. George Harley : London Lancet, March 3, 1888. 



PHYSIOLOGY AND HEALTH. 69 

Food taken under these circumstances may lie entirely 
unchanged in the stomach until it is thrown off from it. 

(e) The mind should be at rest during a meal. The 
man who has an after-dinner speech to make is liable 
to have indigestion. Hard thinking or studying should 
be discontinued at the table, and cheerful conversation 
and light thought should take their place. 

(f) Ice-water chills the stomach, and should not be 
taken during a meal. It is best to abstain from all drink 
w r hile eating. Too much liquid dilutes and weakens the 
gastric juice. 

(g) Observe regular hours for meals. Take two or 
three or four meals a day according to circumstances; 
but let them be at fixed times, Irregular eating tires 
and w T eakens the stomach. 



ILLUSTRATIONS. 

1. Pupils can study the teeth in their own mouths and those 
of their companions. The alimentary canal of a bird, or some 
other small animal, will give a general idea of this tube. To show 
how fats are prepared for digestion, make an emulsion of fat with 
the white of an egg, or a weak solution of gum acacia, and com- 
pare it with a mixture of fat in water. 



QUESTIONS. 

I 

1. Name a property of living things that distinguishes them 
from not-living things. 

2. Can not-living things grow ? 

3. What is growth by accretion ? What is growth by assimi- 
lation ? 

4. 5. How are substances taken into the body? 



70 UNION SERIES, NO. 3. 

6, 7. What is the alimentary canal ? What are its appendages? 

8. How long is the alimentary canal? 

9. What are its divisions? 

10. What is the width of the alimentary canal ? 

11. What is the use of the muscle-fibers in the wall of the 
alimentary canal? 

12. Describe the lining of the alimentary canal. 

13. Has a newborn infant any teeth ? How many teeth in the 
first set, and how are they named ? 

14. When do the second set come? 

15. State the number and the names of the second teeth. 

16. What purposes do the different kinds of teeth serve? 

17. Are the teeth true bones? Describe the different parts of 
a tooth. 

18. How may the teeth be injured ? How should they be cared 
for? 

19. What is the result of neglect of the teeth? 

20. What is the work of the tongue? How is it fitted for this 
work ? 

21. Describe the throat, and the openings into and out from it. 

22. Describe the gullet. 

23. What is the stomach? How may indigestion seem to be 
heart disease? 

24. What is the position of the stomach in an adult? in an 
infant ? 

25. What muscle-fibers are in the walls of the stomach ? 

26. Describe the lining of the stomach ? 

27. What is the pylorus? What is its work? How long is the 
small intestine? the large intestine? What is the duodenum? 
What work is done in the intestines? 

II 

1. What is a "gland?" JSame some of the glands and their 
work. 

2. Name the salivary glands, and tell where they are situated. 

3. What is the structure of the salivary glands? 

4. Describe the saliva. 

5. Give the size and location of the liver. 



PHYSIOLOGY AND HEALTH. 71 

6. Describe the gall-bladder and its work. 

7. What is the work of the liver ? 

8. What happens if the bile-duct is stopped ? 

9. What is glycogen ? 

10. Describe the pancreas. How much fluid does it secrete 

daily ? 

J in 

1. What is digestion? 

2. In what two ways is food acted on in digestion ? 

3. W T hy is it important to chew food thoroughly ? 

4. What is the work of saliva? 

5. Does saliva flow when we are not eating? How much is 
poured out in twenty-four hours ? 

6. Describe the act of swallowing. 

7. What takes place in the stomach when the food arrives 
there ? 

8. What parts of the food are digested in the stomach ? 

9. What happens if the gastric juice is poor or scanty? 

10. What is chyme? 

11. Where are starchy matters digested ? Where is fat digested ? 
What fluids digest starch and fats? 

12. What is an emulsion ? 

13. 14. Where is meat chiefly digested? bread? butter? 

IV 

1. What is the sensation caused by alcohol in the mouth? 

2. What is the chemical action of alcohol ? 

3. 4. What effect has alcohol on gastric juice ? 

5. What effects of alcohol did Dr. Beaumont observe in the 
stomach of Saint-Martin? 

6, 7, 8. Does alcohol ever cause dyspepsia ? 

9. Describe its effect on the stomach. 

10. Does the drinker learn to dislike the drink that is injuring 
him ? 

11. 12. What is the effect of alcohol on the intestines? on the 

liver ? 

v 

1. How may dyspepsia be acquired? 

2. Give some rules for avoiding dyspepsia? 



72 UNION SERIES, NO. 3. 



CHAPTER VI. 



ABSORPTION. -THE BLOOD. -THE LYMPHATICS. 



1. In the preceding chapter we studied the first part 
of the process of Assimilation, namely, digestion. This 
is the preparing of food in the alimentary canal to be 
taken into the blood. 

2. The alimentary canal is a closed tube. It has been 
likened to a kitchen, where food is dressed and cooked. 
But a kitchen has a door and halls leading from it, by 
which food may be carried to all parts of the house. 
The alimentary canal has no openings through its 
walls, except ducts of the salivary glands, the liver and 
pancreas. How, then, does digested food pass through? 

3. It soaks through. If you fill a glass bottle with 
water and put a stopper in, not a particle of water will 
come to the outside. It is water-tight. But if you fill a 
leathern-bag with water, drops will be seen on the outside 
surface. In this respect the alimentary canal is like a 
leathern-bag. 

4. In the wall of the alimentary canal are innumer- 
able very small blood-vessels, with walls thinner than 
tissue-paper. They are there for the purpose of taking 
up the liquid food, as it soaks out of the alimentary 
canal. It soaks into them, just as water will soak through 
a kid-glove and wet your fingers inside. 



PHYSIOLOGY AND HEALTH. 



73 



5. In these little blood-vessels the blood is constantly 
moving. So that as the liquid food enters, it is carried 
away directly, and the blood-vessel is ready for more. 
The farmer lays pipes made of tile under ground in a 
wet field, and the water in the soil soaks into them and 
flows off. The water may be said to be " absorbed " by 
the tile-pipes. So digested food is absorbed by the little 
blood-vessels in the wall of the alimentary canal. 

Absorption. 

6. Absorption may take place in any part of the ali- 
mentary canal. Take a piece of sugar in your mouth 
and let it dissolve. A part of it will be absorbed. It 
will pass into the little blood-vessels under the lining 
of the mouth. 

7. There is not much absorption in the throat or 
gullet, because our food passes through them so rapidly. 
Besides, only a small portion of food 
is yet ready to be absorbed. In the 
stomach a part of the animal food 
is absorbed as fast as it is digested. 
Starchy and fatty foods are not ab- 
sorbed there, because they have to 
be prepared farther down. 

8. It is in the small intestines that 
most of the food is absorbed. Here 
the starches and fats are digested, 
starch being turned into sugar and fat 
being mixed in an emulsion. There 
is in the small intestine a special apparatus for absorp- 
tion which will now be described. 

9. If the lining of the small intestine be examined 




74 UNION SERIES, NO. 3. 

with a magnifying glass, it presents a velvety appear- 
ance. This is because it is like velvet, in being covered 
with short, thread-like prominences standing closely to- 
gether as in the nap of cloth. There are thirty or forty 
of them in a square millimeter. They are called villi. 

10. If one of these villi be studied under a microscope, 
it is found to contain a net-work of small blood-vessels 
and a tube which begins here and is connected with a 
set of vessels, called lymphatics. These villi are bathed 
in the liquid food, as the rootlets of a plant are bathed 
in the water of the soil, and they drink up fluid as the 
rootlets do. Nearly all the fat is taken up by the villi, 
and enters into the tube which is connected with the 
fymphatic system. 

11, When the food has reached the lower end of the 
intestine, most of the liquid digested portions have been 
absorbed into the blood-vessels and lymphatics. 

II 

The Blood. 

1. The first step in assimilation is digestion; the 
second step is absorption. The digested fluid has now 
become a part of the blood. That which was a few 
hours before meat, fruit, and bread is now blood. 

2. The blood is a red fluid, saltish in taste, warm 
when it comes from the living animal, soon thickening 
to form a clot. 

The Corpuscles. 

3. If blood be examined with a microscope it is seen 
to consist of a clear and transparent liquid, with numer- 
ous little globules floating in it. These globules give it 



PHYSIOLOGY AND HEALTH. 



75 




a red color. They constitute about half of the blood, and 
are commonly called the blood corpuscles. Most of 
them are of an amber color, when 
seen one at a time, but when gathered 
in a mass they are red. About one 
in four to six hundred is white. 

4. The white corpuscles are spheri- 
cal in shape. The red corpuscles are 
shaped like two saucers, placed back to back. They are 
thinner at the center than at the circumference. 

5. All animals with a backbone (vertebrates) have 
red blood corpuscles. But the shape of these is different 

in different classes. In 
H birds, reptiles, and fishes 
the corpuscles are oval. 
In the class mammals, to 
which man belongs, they 
are round and flattened. 
It is easy to determine, 
by examining a drop of 

blood with a microscope, whether it came from a mammal 

or not. 

6. We can determine from such an examination whether 
a drop of blood came from a human being, or one of the 
lower members of the order of mammals. For all of our 
domestic animals, except fowls, are mammals, and have 
round corpuscles. The corpuscles of each species of ani- 
mals are almost precisely uniform in size; and no two 
species have corpuscles of the same size. There are only 
a few mammals whose corpuscles are as large as man's. 
The huge elephant and the whale have corpuscles a little 
larger, and so have three or four other mammals. But 




76 UNION SERIES, NO. 3. 

dogs, cats, sheep, oxen, horses, — in short, all the ani- 
mals that are in this country associated with man have 
smaller corpuscles. 

7. The red corpuscles in man measure 1.3200 of an 
inch (7.9 mmm -) in diameter. Those of the dog, the nearest 
in size to mankind in our domestic animals, are 1.3500 
(7.25 mmm -). 

8. Ordinarily, therefore, an expert microscopist could 
determine whether a blood-stain were from human blood 
or not. For even though the stain is dried, it can be 
carefully soaked out, so that its corpuscles can be restored 
to their natural size. But where human life is at stake, 
testimony depending on such nice measurement should 
be received with caution. 

9. The red and white corpuscles go rolling along in 
the blood stream, and when they are crowded in a very 
small blood-vessel, they yield and change their shape. 
But they are elastic, and resume their natural shape as 
soon as they are out of the crowd. 

10. The red corpuscles have, for their special work, to 
carry oxygen from the lungs to every part of the body. 
Oxygen is the King of the Elements, and these are his 
royal chariots. When they leave the lungs they are full 
of oxygen, and are bright-scarlet. When they come back 
to the lungs they have given up much of their oxygen, 
and are purplish-red. It is the presence or absence of 
oxygen that makes this change in color. 

11. People in good health have an abundance of red 
corpuscles, and these take up oxygen, which colors them 
scarlet. The blood in the blood-vessels of the skin gives 
the skin its rosy hue. 

12. People in poor health often have too few red cor- 






PHYSIOLOGY AND HEALTH. 77 

puscles, and the blood has little color, and the cheeks 
and even the lips are pale. 

13. In many cases the very best remedy is fresh air 
and exercise. Take in oxygen, and make it fly through 
the arteries and veins by active work or play, and your 
cheeks will soon take on color. But sometimes medical 
help and advice are needed. 

The Plasma. 

14. The liquid part of the blood is called the plasma. 
It contains nutritive matter formed from the digested 
food. The digested food is changed as it is absorbed. 
We find, for example, very little fat in the blood, though 
the animal is eating much fat and is growing fat. The 
elements of the fat are there however. 

15. We find very little sugar in the blood. Although 
a person may be eating a great deal of it, and although 
all the starchy foods are changed into sugar in diges- 
tion, it becomes a part of the blood when it is absorbed 
and is no longer sugar. 

16. Eight-tenths of the blood is water. The various 
mineral substances — phosphates, sulphates, and chlorides 

— that we take in our food are found in the blood. In 
its course through the body it is constantly changing its 
constitution, like a river that takes up matter here and 
deposits it there. 

17. It is from the very smallest of the blood-vessels 

— the capillaries — that the nutritive matter gained from 
the .food passes out to the tissues. The blood feeds upon 
the digested food, and the tissues feed upon the nutritive 
matter in the blood. This nutritive matter passes out 
of the blood-vessels in the same way that it passes 



78 UNION SERIES, NO. 3. 

into them. It soaks out. It bathes the surrounding par- 
ticles of flesh, or nerve, or skin, or whatever they may 
be. They take it into themselves, and their strength is 
renewed. This is the final step in the process of assimi- 
lation. It is the tissues, the little particles of the body, 
that assimilate the food finally, and so the life of the 
whole body is maintained. 

18. We have then, — 

Digestion. Circulation. 

Absorption. Transudation. 

Assimilation. 

The four preliminary steps being fairly included with 
the fifth under the general term, assimilation. 

19. The tissues are built up by the food assimilated. 
At the same time they are continually breaking down. 
These two acts go on together. As new matter is brought 
in, the old waste matter must be given out. Life in the 
tissues of the body is accompanied by a kind of com- 
bustion. The food is the fuel, and the waste matters are 
the dust and ashes. The latter must be carried away, 
or the fire w T ill not burn. So one great work of the blood 
is to carry away waste matter from the tissues. The waste 
matter gets into the blood as food does. It soaks in at 
the same time that nutritive matter soaks out from the 
capillaries. And it is sw^ept along to be finally cast out 
of the body by the lungs, the skin, or the kidneys. 

Coagulation of the Blood. 

20. Blood flows from a cut freely at first. This 
naturally causes some alarm in the lookers-on. For we 
know that " the blood is the life," and when we see the 



PHYSIOLOGY AND HEALTH. 79 

crimson stream we feel that the life is ebbing away. 
Many turn faint and sick at the sight; and probably 
every serious cut would be fatal, but for a remarkable 
provision which Nature has made to guard against such 
a result. 

21. Fresh blood, after being exposed to the air for 
a few seconds, begins to grow thick. In ten minutes 
it has changed from a fluid to a jelly. This is called 
coagulation. 

22. When a cut has been received, the blood which 
at first is running fast soon thickens, and its flow is 
thus checked. The little blood-vessels become plugged-up 
and the whole cut is often filled with this jelly-like clot. 
This will usually take place even if the cut is left entirely 
alone, if it is not too serious. But blood coagulates more 
readily when it is flowing slowly than when it is flow- 
ing fast. So we help nature by putting a bandage over 
the wound, or pressing it with our fingers. Of course 
when very large blood-vessels are cut, they must be 
immediately closed by pressure, or by tying a thread 
around them. 

23. This must be done by some one who is skillful. 
But any one can press the lips of a wound together. 
While waiting for a physician, a handkerchief can be 
tied about the hurt above the wound. Sometimes it is 
needful to tie one below the wound also. 

Ill 

The Lymphatics. 

1. There is a set of vessels found in close connec- 
tion with the blood-vessels, called the lymphatics. These 



80 



UXION SERIES, NO. 3. 



begin as the finest of spaces and channels in the tissues. 
Hair-like tubes, with very thin walls, lead from these 
spaces and channels. These tubes unite to make larger 

tubes. These again unite, and so 
on until they end in two main 
tubes, each half the size of a lead 
pencil. These main tubes are 
called the thoracic duct and the 
right lymphatic duct. They empty 
into the great veins at the root of 
the neck. 

2. These tubes carry their con- 
tents only in one direction, — 
namely, towards the heart, differ- 
ing in this respect from the blood- 
vessels. They are found just under 
the skin, and in the deeper parts 
of the body. 

3. They are like drain-pipes. 
Their work is to take up the fluid 
which has soaked out of the small 
blood-vessels and which bathes the 
tissues, and carry it away to pour 
it finally into the blood again. 

4. The tubes that are found 
associated with the blood-vessels 

in the villi, in the lining of the small intestine, are lym- 
phatics. They take up fat, and during digestion are 
milky in appearance. Hence they are called lacteals 
(lac, milk). When there is no fat in the intestine they 
look like other lymphatics, and are doing the same kind 
of work. 




PHYSIOLOGY AND HEALTH. 



81 




5. In the course of the lymphatic vessels are many 
little kernels, some as large as a grain of wheat, some 
as large as a bean, through 
which the vessels appear to 
pass. Those which lie under- 
neath the skin can be felt 
in some places. In the neck 
and elsewhere they some- 
times become inflamed and 
swell to a great size. They 
are called lymphatic glands. 

6. The fluid, which is cal- 
led lymph, passes through 
the lymphatic vessels. It is 
colorless, and is much like 
the plasma of the blood in 
composition. In dropsy the lymphatics are unable to do 
their work, and the tissues are filled almost to bursting 
with this fluid. 

IV 

Pure and Impure Blood. 

1. Pure blood is blood that contains the ingredients 
which properly belong to it, and no others. 

2. The blood of one who eats too much will be over- 
loaded with matter from the food, which cannot be used 
by the tissues, and it thus becomes impure. 

3. The blood of an indolent person, who takes no 
exercise, will be likely to become impure. It will not 
have oxygen enough. Moving slowly all the time, it 
will not get rid of its waste matters fast enough, and will 
be likely to be overloaded with food matters. 



82 UNION SERIES, NO. 3. 

4. The blood of one who eats too rich or highly 
seasoned food will be impure. 

5. The blood of one who spends much of his time in 
bad air will be impure. 

6. The blood of one who uses tobacco contains the 
poison nicotine. 

7. The blood of one who uses intoxicating drinks 
contains the poison alcohol. 



Effects of Narcotics on the Blood and Tissues. 

1. Alcohol passes from the stomach into the blood. 
Now we have seen how alcohol hardens or coagulates 
the albumen of the food in the stomach, and hinders 
its digestion. It affects in the same way the albumen 
in the blood, and thus makes the blood much poorer in 
quality for feeding all the tissues of the body, which 
depend upon it for their nourishment. In sufficient 
quantities alcohol injures the blood corpuscles, and thus 
lessens their power of absorbing oxygen. In this way 
it hinders the processes by which the blood is purified. 
The blood of a drinking man is often found, upon exam- 
ination with the microscope, to be loaded with fat as well 
as with other impurities. Since the blood goes to all 
parts of the body, carrying whatever is in it wherever 
it goes, these impurities are carried also, causing disease. 
The alcohol does not become a part of the blood, as the 
food does, but is carried by the blood unchanged to all 
parts of the system, and is the same poisonous sub- 
stance that it was when first taken into the stomach. It 
injures not only the blood but every tissue to which the 
blood carries it. 



PHYSIOLOGY AND HEALTH. 83 

ILLUSTRATIONS. 

1. Illustrate absorption with an earthen flower-pot, or a brick, 
or a glove-finger. 

2. To show blood corpuscles wind a handkerchief tightly around 
a ringer, and with a slight prick draw a drop of blood. Take this 
off on a glass slide, and with the edge of another slide or a 
knife-back, spread the blood so thin that it shows little color. 
Examine with a magnifying power of three or four hundred 
diameters. 

3. If blood can be obtained from the butcher, the clot can be 
shown and the serum which separates from it. 



QUESTIONS. 



1. What is the first step in the process of assimilation? 

2. Is there any passage way from the alimentary canal to the 
blood-vessels ? 

3. How does digested food get out of the alimentary canal? 

4. 5, What is absorption? 

6, 7, 8. In what part of the alimentary canal does absorption 
take place? 

9, What are the villi f 

10, 11. Describe the villi and their work? 

ii 

1. What is the second step in the process of assimilation? 

2. Describe the blood. 

3. What are the corpuscles of the blood? What two kinds 
are there? 

4. What is the shape of each kind? 

5. What division of the animal kingdom has red blood cor- 
puscles? Is the shape of these the same in all animals? 

6. Is the size of the red corpuscle the same in all animals? 

7. What is the size of man's red corpuscles ? of the dogs ? 



84 UNION SERIES, NO. 8. 

8. How can an expert determine to what animal a drop of 
blood belongs? 

9. How do the corpuscles behave when crowded? 

10. What is the work of the red corpuscles? 

11. 12. How does the color of the face indicate the state of 
health ? 

13. What is a good remedy for poor blood? 

14, 15. What is the plasma of the blood? Do we find much 
fat or sugar in the blood? 16. What proportion of the blood is 
water? What mineral substances are found in the blood? 

17. How does nutritive matter finally reach the tissues ? 

18. What five processes are included under the general term 
assimilation? 

19. How is life in the tissues like a combustion? What has 
the blood to do besides bringing nourishment to the tissues? 

20. 21. What is the coagulation of the blood? How is it a 
safeguard ? 

22, 23. How may coagulation in a wound be aided. 

in 

1. Describe the lymp'hatics. 

2. What difference between the course of the lymphatics and of 
the bloodvessels? 

3. What is the work of the lymphatics? 

4. Why are some of them called lacteals ? 

5. What are the lymphatic glands ? 

5. What is lymph? Why does the body swell in dropsy? 



1. What is pure blood? 

2, 3, 4, 5, 6, 7. Name six causes of impurity of the blood. 



1. What effect has alcohol on digested food? on the blood cor- 
puscles? Does alcohol become part of the blood? How does it 
make the blood impure? 



PHYSIOLOGY AND HEALTH. 85 



CHAPTER VII. 



THE HEART AND BLOOD -VESSELS. -THE 
CIRCULATION. 



1. There are in the body of a grown person six or 
eight quarts of blood. It does not fill the spaces in the 
tissues, as water fills the spaces in a sponge, but is con- 
fined to tubes called blood-vessels. Some of these are 
large and many are small. The small ones are so small 
that they are called capillaries (capilla, a hair), and they 
are smaller than hairs. They cannot be seen without 
a magnifying glass. The capillaries penetrate every par- 
ticle of living tissue, and they are so numerous and so 
near together that you cannot put a needle-point in the 
flesh without piercing some of them. 

2. A leaf is sometimes treated with chemicals, which 
eat out all the soft, green parts and leave only the ribs 
and the connecting fibers between them, — the frame-work. 
The result is exquisitely delicate, and is called a skeleton 
leaf. If the body of an animal could be treated in a 
similar way with something that would eat out every- 
thing except the blood-vessels, we should still have a 
perfect figure, every organ being represented by a net- 
work of extreme fineness. 

3. The heart and the blood-vessels are the circulatory 
apparatus. The blood is the medium by which nour- 



86 UNION SERIES, NO. 3. 

ishment gets to the tissues, and by which waste matter 
from the tissues reaches the organs that throw it out. 
It may be looked on as the channel of communication 
between different portions of the body, by which they 
are enabled to work together, as railroads or rivers and 
canals are the means of communication between different 
parts of the same country. 

4. The body, with its parts and organs, may be com- 
pared to a country with its provinces or states. If the 
steam-cars stop running and the canals and rivers are 
closed, much of the business of the country must be at a 
stand-still. So when the blood stops flowing, the life of 
the body and its organs must cease. 

Fainting. 

5. The more delicate and sensitive the organ, the 
more dependent it is on a permanent suppty of blood. 
The brain, for example, is said to have about one- 
fifth part of the blood in the body. If, for an instant, 
the heart stops beating, or beats very feebly, the brain 
is affected. The person becomes unconscious and falls. 
This is a fainting fit. The action of the brain stops, 
because it is not getting its customary supply of blood. 

6. When, therefore, any one faints, the proper thing 
to do is, — 

(a) Give him fresh air. This will stimulate the heart. 
The worst thing to do is to crowd about him, and shut 
off the air. 

(6) Lay him on his back. In the horizontal position 
the blood flows to the head much more readily than in 
the upright position. Do not lift him up. 

(c) If these measures are not sufficient, sprinkle a 



PHYSIOLOGY AND HEALTH. 



little cold water on his face, tickle his nose with a fine 
feather, or hold a bottle of smelling salts to it. The 
heart can be' roused to action by adopting methods like 
these. As soon as it is beating with its ordinary strength 
and frequency, the brain resumes its control. 



The Heart. 

7. The heart is made of muscle, and is as large as 
the fist. It is shaped like a pear, and lies in the chest, 
more of it on the left than on 
the right side. The point, 
or apex, is between the fifth 
and sixth ribs, and the base, 
which looks upward and to 
the right, extends as high 
as the third rib. It lies upon 
the diaphragm, and is held 
up by the great blood-vessels 
which are attached to it. 

8. The heart is incased 
in a loose sac, called the 
pericardium. This has a 
very smooth lining, which is always slightly moist, so 
that as the heart moves there is no friction. 

9. The heart is hollow, and its interior is divided by 
a partition extending from base to apex into a right 
and left half which have no direct connection with each 
other. These halves are sometimes spoken of as the right 
and left heart, as though they were entirely separate. 

10. Each half is again divided into two chambers, 
an auricle and a ventricle. The auricle is at the broad 
end, and has walls not more than one-twelfth of an inch 




UNION SERIES, NO. 3. 



(2 mm ) in thickness, The ventricle extends to the apex, 
and has thicker walls. The walls of the right ventricle 
are one-sixth of an inch (4 mm ) in thickness. The walls 
of the left ventricle are half an inch (12 mm -) in thickness. 
The capacity of these chambers is about the same. Each 
will hold from three to six ounces (85 to 170 cc -) of fluid. 

11. There is no direct communication between the 
right and left sides of the heart, but each auricle com- 
municates with the ventricle, on the same side, by a 
round opening an inch (25 mm -) in diameter. These open- 
ings are closed by valves: that in the right side being 
the tricuspid, or three-pointed ; that in the left side the 
mitral (like a miter). These valves are flaps made of 
the lining membrane of the heart. They are thin, but 
strong. They open like folding-doors into the ventricle 
when the blood is passing through. If it flows back, 
they close as folding-doors close when a crowd is push- 
ing against them in the wrong direction. Fine, tough 
cords are attached to their edges and to the sides of the 
cavity of the ventricle, which keeps them from opening 
back into the auricle. 

The Blood-Vessels. 

12. The blood-vessels leave the heart and extend to 
every part of the body, and then return to the heart. 
They differ in size in the structure of their walls, and in 
the part they have to perform in the circulation. 

13. From the right ventricle one large artery curves 
off, the pulmonary artery. This soon divides into two 
great branches, one of which goes to the right lung, 
the other to the left lung. As these branches enter the 
lung they divide again and again, as a limb of a tree 



PHYSIOLOGY AND HEALTH. 



89 



divides into branches and twigs, these growing smaller 
as they divide. 

14. At the same time their coats grow thinner. The 
smallest divisions are not more than one-three-thousandth 
of an inch (8 mmm -) in diameter, and their walls are thin- 
ner than the thinnest tissue-paper. They are called capil- 
laries. The capillaries are short but innumerable, and 
make a close net-work around the air-cells of the lung. 
Many capillaries combine to form a vein. Small veins 
unite to form larger ones, until all the veins in each lung 
have joined in one or two large veins, called pulmonary 
veins, which empty into the left auricle of the heart. We 
started from the right ventricle, followed the blood-vessels 
through the lungs, and return to the left auricle. 

15. From the left ventricle the blood is driven into the 
aorta, a great artery, which runs down beside the back- 
bone. From the aorta branches are 
given off to the head, and to the 
upper limbs and to the trunk. At 
the lower part of the backbone the 
aorta divides into large branches 
that supply the lower limbs. 

16. If we follow any of these 
branches we shall find them divid- 
ing again and again, just as in the 
lungs, until we come to the capil- 
laries, and then to the veins, which 
all finally join in two great veins, 
called respectively the superior and 
inferior vena cava. These empty into the right auricle. 

17. We have therefore two sets of vessels, one of w T hich 
goes through the lungs and constitutes what is called the 




90 



UNION SERIES, NO. 3. 



pulmonary circulation, while the other goes through the 
rest of the body and constitutes the general circulation. 
These, however, are not separate, but connected through 
the openings between the auricles and ventricles. 



Work of the Heart. 

18. The heart beats from sixty-five to seventy-five 
times a minute in a grown person. This beat which can 
be heard with the ear on the chest, and can be seen over 
the point of the heart, is caused by a sudden contraction 
of its walls. The heart is made of muscle-fibers, and 
these have a fixed habit of contracting forcibly so many 
times in a minute. The blood in its cavities is in that 
way driven out at each beat, as water is forced through 
a rubber syringe by squeezing its bulb. 

19. A rubber syringe has little metal valves, which 
prevent the water from pouring backward when the bulb 

is squeezed. The valves of the heart, 
the tricuspid and mitral, answer the 
same purpose. 

20. Follow the course of the blood 
through the heart. Remember that 
the heart is a double organ, the right 
and left side each propelling its own 
stream. The blood enters the right 
auricle through the vena cava superior 
and the vena cava inferior. It enters 
the left auricle at the same time through the pulmonary 
veins. At this time the muscle is relaxed, and the 
cavities are wide open to receive the blood flowing freely 
through them. Suddenly the auricles contract with a 




PHYSIOLOGY AND HEALTH. 91 

quick movement and throw the blood through the open- 
ings, which lead to the ventricles." The valves are wide 
open. Next the ventricles contract. The blood pushes 
the valves up, and they come together so that nothing 
can pass back into the auricles. The stream must go 
forward, and it enters from the right ventricle, the pul- 
monary artery, from the left ventricle, the aorta. At 
the commencement of each of these great vessels are 
valves (the semi-lunar valves), somewhat like those 
in the heart, which close after the blood has passed 
through, and prevent its flowing back into the ventricle 
during the period of relaxation, which directly follows 
its contraction. 

21. This is the process which is repeated sixty-five to 
seventy-five times a minute during life. This is the force 
that keeps the blood flowing through arteries and capil- 
laries and veins throughout the body. The circulation 
depends mainly on the heart. 

22. The heart has in itself the power of contracting 
and relaxing in this way. A frog's heart will contract 
for some time after it is taken out of the body. The 
action of the heart is regulated in the living body by 
nerves. 

23. The sounds of the heart are two short, quick 
sounds, one rapidly succeeding the other. They may be 
heard by listening over the apex. The first sound is 
caused by the sudden closing of the valves of the heart. 
The second, which is shorter and higher pitched, is 
caused by the closing of the semi-lunar valves in the 
great blood-vessels. 

24. The heart does not stop by night or by day. Arms 
and legs become exhausted, and must have long rest ; 



92 UNION SERIES, NO. 8. 

but the heart gets its rest in the little interval between 
its contractions, and that appears to be sufficient for it 
Indeed, if all these short periods of repose are added 
.together, they will amount to ten or twelve hours in 
twenty-four. The heart never feels tired if we are well. 
It has been estimated that the work done by the heart 
in twenty-four hours is enough to raise three hundred 
tons weight one foot from the ground. 

25. The beating of a healthy heart is perfectly regular, 
but in some disorders it becomes irregular and intermit- 
tent. It beats now fast and now slow, and often skips a 
beat. "Smoker's heart," caused by the use of tobacco, 
acts in this way. 

26. Palpitation of the heart is a rapid, hard beating 
which is very distressing. It is an indication of weak- 
ness, but not necessarily of any heart disease. It is often 
caused by indigestion. 

27. Sometimes the lining of the heart and the great 
arteries become inflamed. The valves, which are folds of 
this lining, become thickened and hardened. They no 
longer close accurately and when they open they, by their 
size and roughness, obstruct the flow of the blood. When 
the valves of a pump become stiff and worn-out, the pump 
is of little use. So a heart affected in this way works 
badly, and is liable to stop working suddenly. This is 
heart disease. 

II 

Work of the Blood-Vessels. 

1. The vessels that carry blood away from the heart 
are called arteries. Those which carry blood back to the 
heart are veins. The small, thin, walled vessels which fill 



PHYSIOLOGY AND HEALTH. 93 

the tissues and connect the arteries with the veins are the 
capillaries. 

2. The arteries are very elastic. When blood is 
thrown into the aorta, it stretches and then contracts, so 
helping to hurry the stream along. 

The Pulse. 

3. It is this elasticity of the arterial walls that makes 
the pulse. The pulse is a beating of an artery which can 
be felt by the finger-end laid upon it. Sometimes the 
pulse can be seen, as in the temple or the neck. It can be 
felt wherever an artery lies near the surface of the body. 
The artery on the thumb side of the wrist is the one 
commonly sought for by the physician, because it is easy 
to find. 

4. From the pulse the physician learns how many 
times the heart is beating each minute. The usual num- 
ber has been estimated as follows : — 

At birth 130 to 140 

First year 115 to 130 

Second year .... 100 to 115 

Third year 90 to 100 

Tenth year 85 to 90 

Fourteenth year . . . . 80 to 85 

Adult life 65 to 75 

5. The number of heart-beats varies at different times 
in the day. It is greater in the morning and after eating. 
It is less in sleep and in the recumbent posture. It is 
increased by excitement and by heat, Each person has 
a standard number of beats per minute, and it is well 
for each to find out what it is, that the physician who 



94 UNION SERIES, NO. 3. 

is called when sickness comes may know how much the 
heart is departing from its proper action. 

6. The physician likewise learns from the pulse how 
strong the heart-beat is, how full the arteries are, and 
whether their walls are hard or soft. All these things 
inform the skillful observer as to the state of the system 
and the remedies required. 

7. Near the heart the pulse is very strong and quick. 
Farther away from the heart the pulse is less marked. If 
an artery be cut near the heart, the blood comes in spurts 
at every heart-beat. If an artery some distance away 
from the heart be cut, the stream is more even. From the 
capillaries and veins it is steady, with no spurting. In 
these vessels there is no pulse. If the blood flows from 
a wound in jets which keep time with the heart-beat, it 
is certain that an artery has been cut. If it flows in a 
continuous stream, it is from a vein. 

The Capillaries. 

8. The capillaries are the most important of the 
blood-vessels. The work of the arteries is to carry blood 
to the capillaries, and the work of the veins is to carry 
blood from the capillaries. It is the capillaries, with 
their thin walls, that permit nourishment from the blood 
to soak out and bathe the tissues, and the capillaries 
take up carbon dioxide and other waste matters from the 
tissues. The capillaries are very small, but they are so 
numerous that if they were all put together to make one 
large tube, this would be three hundred times as wide 
as the great arteries (aorta and pulmonary) which come 
from the heart. ' 



PHYSIOLOGY AND HEALTH. 95 

9. Since the blood stream widens so much in the 
capillaries, it must flow more slowly in them, as a river 
flows more slowly when it widens out than when it is 
rushing between narrow banks. In the aorta the blood 
flows at the rate of ten inches (254 mm *) in a second. In 
the capillaries it flows at the rate of one-fiftieth (.5™**-) 
of an inch in a second. 

The Veins. 

10. The capillaries are continued by the veins. These 
are more numerous than the arteries. Consequently they 
are not so full, and the blood flows more slowly in them. 
Their walls are not so thick nor so elastic as those of the 
arteries, but they are very strong. 

11. There are certain parts in the veins that we do not 
find in the arteries, namely, the valves. These valves are 
flaps of the lining membrane, similar to those already 
described, which stand out like little pockets. These 
pockets open in the direction in which the blood is flow- 
ing, and lie flat against the wall of the vessel. If any 
thing makes the current of blood set back, the pockets 
fill and bulge out and stop the backward flow. Valves 
are not needed in the arteries except at their very begin- 
ning, because the heart keeps forcing the current along. 
But in the veins they are useful. 

12. Experiments on animals have shown that it takes 
about twenty seconds for the blood to go from the heart 
through arteries and capillaries and veins back to the 
heart again. 

Regulation of the Circulation. 

13. Both arteries and veins have muscle-fibers in their 
walls which run crosswise and surround the tube. When 



96 UNION SERIES, NO. 3. 

these fibers contract it makes the tube smaller, and thus 
presses out a part of the blood in it. When they expand 
they make the tube larger, and more blood flows through 
them. Nerves in these muscles make them contract 
and expand, thus regulating their size and the amount 
of blood they can retain. This is a very important 
provision. The heart also has its controlling nerves, one 
of which, called the inhibitory nerve, has a restraining 
influence upon the heart's action. If this nerve is cut the 
heart begins at once to beat rapidly and tumultuously. 

14. It is not sufficient that the blood should be car- 
ried through, the body in an even stream, as water flows 
through the city supply-pipes, always taking as much 
to one place as to another. There must be in the animal 
body some way of regulating the supply. When any 
organ is acting vigorously, it needs more blood than it 
does when it is at rest. If the brain, for example, would 
go to sleep, the supply of blood to it must be for the 
time diminished. While it continues to flow in a full 
stream we cannot sleep. An abundance of blood in any 
part stimulates that part. If the muscles are actively 
exercising, they need a larger supply of blood, and it 
must be drawn off from other parts. We feel disin- 
clined to hard exercise immediately after a hearty meal, 
because then the blood is in the walls of the stomach 
and is turned off in part from the muscles. 

15. While therefore every part of the body must have 
blood all the time, no part wants the same amount all 
the time. And the supply to any part is regulated by the 
contraction or expansion of the arteries in that region. 
The arteries are controlled by the nervous system. 

16. When the bodv is inactive the circulation becomes 



PHYSIOLOGY AND HEALTH. 97 

sluggish. Then the tissues are not supplied with fresh 
oxygen as fast as they need it, and the waste matter is 
not promptly removed. This makes the mind dull and 
the body liable to disease. 

17. Physical exercise is necessary to keep body and 
mind in good condition. Playing ball or tennis, boat- 
ing, riding, and other out-of-door sports, keep the circu- 
lation active. 

Ill 

Effects of Alcohol on the Heart and Blood-Vessels. 

1. The beating of the heart is very quickly affected 
by any disturbance in the nerves which should control 
its beats. Alcohol, by its power to deaden these nerves, 
is a serious heart disturber. A small quantity taken 
into the blood quickly paralyzes the inhibitory nerve, 
whose office, as we have seen, is to hold the heart in 
check. The heart at once begins to beat faster, just as 
it would if this nerve were entirely cut off from all 
connection with the heart, 

2. The amount of work which the heart does in 
health is almost incredible. To increase that amount, 
by making the heart beat faster than it should, is to 
put unnecessary and extra strain upon an organ whose 
healthy condition is essential to life. A couple of glasses 
of wine, by paralyzing the inhibitory nerve of the heart, 
will sometimes increase its beats from three to four 
strokes per minute. Calculating the weight of blood 
which the heart lifts at each beat at about six ounces, 
four extra beats every minute would cause it to lift ninety 
extra pounds of blood in an hour, which w r ould amount 
to over a ton in the course of twenty-four hours. 



98 UNION SERIES, NO. 3. 

3. When a person sits or lies down, the heart does 
not need to lift so much blood as when he is standing 
or walking. It does not therefore beat so frequently, 
and thus gains some additional time for rest. This is 
one of Nature's wise provisions to give the heart rest 
while other parts of the body are resting. But the man 
who goes to bed with a glass of beer or wine circulating 
through his blood paralyzes, to a greater or less extent, 
the inhibitory nerve of his heart, and this causes that 
organ to keep beating at a rapid rate when it should be 
beating at a slow one. In this way he deprives his heart 
of the rest it needs. It is not strange, therefore, that the 
moderate drinker frequently has " heart trouble." 

4. We have seen that the blood of the drinker is 
often overcharged with fat. The heart is very liable to 
be a place of deposit for such extra fat, especially if it 
is at the same time weakened by overwork. The fat 
may collect in such quantities upon the outside as to 
press upon the muscles of which the heart is composed, 
and in time cause injurious changes in them ; or the 
fat in the blood may be lodged between the layers of 
muscle, and crowd upon these until they become weak- 
ened and changed to fat themselves. Sometimes alco- 
hol causes the muscular walls of the heart to thicken 
and encroach upon the cavities until they cannot hold 
their due amount of blood ; or it may cause them to 
grow thin. Then the cavities of the heart become too 
large. It may cause deposits of fatty or earthy sub- 
stances in the muscular walls of the heart, making them 
liable to rupture from any unusual strain. A like dan- 
gerous change takes place very often in the arteries of 
the habitual drinker. Instead of being soft and elastic, 



PHYSIOLOGY AND HEALTH. 99 

the walls of the arteries become hard and brittle, and 
very liable to burst at any moment. Cases of sudden 
death from this cause in intemperate people are fre- 
quently reported by physicians, who have made exami- 
nations after death, and found striking illustrations of 
these changes in the coats of the arteries, caused by 
indulgence in alcoholic drinks. 1 

5. As Ave have seen, there are nerves in the w T alls of 
the blood-vessels that cause them to contract and expand. 
Alcohol quickly paralyzes these nerves, and that lets the 
walls of the blood-vessels stretch too much, and more than 
the proper amount of blood rushes into them. The face 
of the drinker becomes flushed soon after he has swal- 
lowed his wine or beer. This is because the nerves in the 
walls of the blood-vessels in his face have been paralyzed 
by alcohol and the vessels have expanded, and too much 
blood has rushed to his face, making it red. This para- 
lyzing action of alcohol on the nerves in the walls of the 
blood-vessels, letting too much blood go to places where 
it should not, is the secret of much harm which alcohol 
does to the bodj r . 

6. The circulation of the right amount of blood 
through the different organs of the body is essential to 
health. Alcohol, by causing the blood-vessels to unduly 
expand, disturbs the proper circulation of the blood. 



ILLUSTRATIONS. 

1. Show a heart and blood-vessels from the butcher's. Pour 
water through it, and show the working of the valves. Cut it open 
and point out the cavities and their openings. 

1 Kupture of the blood-vessels, causing sudden death, is not 
always due to alcoholic drinks. 



100 UNION SERIES, NO. 3. 

2, Pupils can observe in themselves and each other the sounds 
and the movements of the heart, and can find and count the 
pulse. 



QUESTIONS. 



1. How much blood is there in the body? What are the 
capillaries? 

2. Where are the capillaries found? 

3. What is the circulatory apparatus ? What is the use of the 
blood? 

4. Illustrate the work of the blood. 

5. What is a fainting fit? 

6. What should be done for a person w T ho has fainted? 

7. Describe the heart. 

8. Describe the pericardium. 

9. W'hat is meant by the terms right heart and left heart? 

10. What are the auricles of the heart? the ventricles ? What 
is the capacity of each ? 

11. Is there communication between the chambers of the heart? 
Describe the valves of the heart. 

12. What is the course of the blood-vessels? 

13. Follow the pulmonary artery and its branches. 

14. To what vessels does the pulmonary artery lead? What 
vessels carry the blood from the pulmonary artery back to the 
heart? 

15. 16. Starting in the aorta follow the blood in its course until it 
has returned to the heart. 

17. Explain how we may be said to have a double circulation. 
Are the two parts of the heart entirely distinct? 

18, 19. How many times in a minute does the heart beat? 
Describe the action of the heart. 

20. Follow the course of the blood through the heart and de- 
scribe the action of each part. 

21. What is the power that keeps up the circulation ? 

22. How is the action of the heart regulated ? 

23. What are the sounds of the heart? the cause of each? 



PHYSIOLOG Y AND HE A LTH. 101 

24. Does the heart get any rest? How is the work it does 
measured? 

25. What is a " smoker's heart " ? 

26. What is palpitation of the heart? 

27. What is the effect of inflammation of the heart's lining ? 

ii 

1. What are arteries? veins? capillaries? 

2, 3. What is the pulse? W r here may the pulse be felt? 

4. What is the usual rate of the pulse at different periods of 
life? 

5. What natural variation in the rate of the heart-beats? 

6. What does the physician learn by feeling the pulse? 

7. When blood flows from a wound, how can we tell what kind 
of a vessel it comes from ? 

8. What is the work of the capillaries ? What is the combined 
diameter of the capillaries ? 

9. How fast does the blood flow in the aorta ? in the capillaries ? 

10. 11. Describe the veins. 

12. How long does it take for blood to make the circuit of the 
vessels, and return to the heart? 

13. How is the circulation regulated? 

14. 15. Why is it necessary that the supply of blood should be 
regulated ? 

16. What effect has bodily inactivity on the circulation ? 

17. What effects have out-of-door sports on the circulation? 

in 

1. What effect has alcohol on the nerves which control the 
heart? 

2. How much extra work by the heart would four extra beats 
per minute signify ? 

3. How does the heart get its rest? How does alcohol deprive 
it of a portion of its rest? 

4. What effect has alcohol on the walls of the heart and of 
the blood-vessels? 

5. 6. How does alcohol interfere with the proper distribution 
of the blood ? 



102 UNION SERIES, NO. 3. 



CHAPTER VIII. 



RESPIRATION. -AIR. 

I 

1. Besides food and drink, air is required by the body 
for the maintenance of its life. The need for air is more 
pressing than the need for food or drink. It is possible 
to live for many daj r s without drinking, and for weeks 
without eating, but no one can live for five minutes with- 
out breathing. While, therefore, we must exert ourselves 
to procure food, air is supplied to us without limit. 

2. Air is a mixture of gases as follows: in one hun- 
dred parts of pure air, — 

Nitrogen about . . . .79 
Oxygen " .... 20.96 

Carbon dioxide . -. . . .04 



Total 100.00 

Air contains also some vapour of water. We can see the 
water in our breath on a cold day. It gathers in drops 
on the window-pane in a room full of people. 

3. The act of breathing is as constant as the beating 
of the heart. If we suspect a motionless figure to be 
dead, we watch for the breathing; for this ceases only 
with life, though at times it may be scarcely perceptible. 

4. With each breath we take in twenty cubic inches 
(327 cc -) of air. Its composition has already been given. 
When this air is breathed out, its composition has been 



PHYSIOLOGY AND HEALTH. 103 

changed. Of the one hundred parts taken in, there is 
returned in expiration, — 

Nitrogen about 79 

Oxygen " .... 16 

Carbonic dioxide .... 4 

Total 99 

5. Comparing this table with the preceding, it appears 
that the amount of nitrogen is unchanged. Almost five 
of the twenty-one parts of oxygen are lost, — that is, 
they are taken up by the bod}'. The carbon dioxide is 
increased one hundred-fold. There is also an increase 
in the amount of watery vapor. The act of breathing 
then gains oxygen for the body from the air, and gives 
carbon dioxide from the body to the air. 

6. The expired air is about one per cent, less in vol- 
ume than the inspired air at the same temperature. In 
other words, the increase in carbon dioxide does not quite 
equal the loss in oxygen, by volume. In weight, how- 
ever, this expired air exceeds the inspired air. We lose 
weight with every breath. Not man alone, but all ani- 
mals, take oxygen from the air and give carbon dioxide 
to the air in breathing. Neither man nor other animals 
take more than a little nitrogen from the air, or give it 
to the air. The use of the nitrogen seems to be to dilute 
the oxygen. The diluted oxygen is better adapted to 
breathing than pure oxygen would be. 

7. Carbon dioxide is for animals a waste substance. 
They cast it out, but do not take it in. For plants it is 
food. Animals take in oxygen and give out carbon 
dioxide; plants take in carbon dioxide and give out 
oxygen. Thus a balance is maintained. 



104 UNION SERIES, NO. 3. 

8. In cities where there is great crowding together of 
people and lower animals, and little vegetation, the air 
contains more carbon dioxide than it does in the country. 
Fires and lights also consume oxygen and make carbon 
dioxide. But air is always in motion, and the forests and 
the ocean keep it pure. 

9. Oxygen is the most active and powerful of all the 
chemical elements. It is also the most abundant, as it 
constitutes about half of the material world. Its activity 
is so great that it has been called the King of the 
Elements and the Life-Giver. 

II 

The Respiratory Apparatus. 

1. Let us now examine the respiratory apparatus. 
This apparatus differs in different animals. The object 
of breathing is the same in all, namely, to take oxygen 
into the body and give up carbon dioxide from the body. 
In the lower kinds of animal life, which have no organs, 
but are simply masses of jelly-like matter, the oxygen 
penetrates from the surface through the whole mass and 
the carbon dioxide passes off from the surface. But in 
higher animals oxygen is first introduced into the blood, 
and by the circulation of the blood is carried to all parts 
of the body. In the same way the carbon dioxide is 
carried from all parts of the body to that part which 
receives the oxygen, and there it is cast out. 

2. In the frog and some other animals the skin is a 
breathing organ. As long as the skin is kept moist oxy- 
gen passes through it to the blood-vessels, and is ex- 
changed for carbon dioxide. In fishes the blood gets its 



PHYSIOLOGY AND HEALTH. . 105 

oxygen in the organs that we call the gills. These are 
thin plates of membrane full of blood-vessels which lie in 
an opening of the neck communicating with the mouth. 
Now water contains a certain amount of air dissolved in 
it, and the oxygen of this air enters the blood of the fish 
in its gills. A fish dies in the air because its gills get 
dry, and that stops its breathing. 

3. In men and other vertebrates, Nature adopts a 
different plan. The skin would not do for a breathing 
organ in a land animal, because it is not sufficiently 
moist. Oxygen and carbon dioxide do not readily pass 
through the membranes of the body when they are dry. 
For the same reason, the blood could not be brought 
to the surface as in the gills of the fish. In an animal 
living in the air, the membranes, through which the 
exchange of gases between the air and the blood takes 
place, must be enclosed in a cavity of the body. Only 
in this way can they be kept moist enough to serve 
their purpose. 

4. The lungs are situated in the chest, and the air is 
brought to them through tubes. The lungs are masses of 
very small air-sacs, at the ends of the air-tubes. These 
masses are penetrated by the blood-vessels which closely 
surround every sac. 

The Respiratory Passages. 

5. The respiratory passages begin at the nose. This 
organ is divided into two parts by a central partition. 
The nostrils open into two narrow passages extending 
back about three inches (76 mm -) ; and ending at the 
upper part of the throat. The nose serves not only for 
breathing but likewise for smelling; the sense of smell 
being situated in the upper part of the nasal passage. 



106 



UNION SERIES, NO. 3. 




6. We can breathe through the mouth, and at times 
it is necessary to do so. But this is not the natural way. 

The nasal cavities 
have moist walls 
close together, and 
the air passing- 
through them is 
warmed and soft- 
ened. The air 
taken in through 
the mouth dries 
the throat, and 
in cold weather 
chills the lungs. Unless there is some obstruction in 
the nose, the habit should be maintained of closing the 
mouth while not speaking. It is a safeguard against 
colds and sore throats to keep the mouth closed, when 
coming out of a warm room into the air, on a cold and 
damp evening. 

7. Snoring is the result of sleeping with the mouth 
open. The soft palate hangs relaxed between the cur- 
rents of air, like a sail in the wind, and rattles in a 
similar fashion. 

The Throat. 

8. The throat is a cavity four inches (10 c - m -) long, 
lying behind the nose and mouth. It has seven open- 
ings into and out from it, — 

(a) The two posterior openings of the nasal cavities. 

(b) The two eustachian tubes from the ear. These 
connect the cavities of the ear, which lie behind the 
drum-head, with the throat. They are as necessary as 



PHYSIOLOGY AND HEALTH. 107 

the hole in the side of a drum. When they become 
closed, as they sometimes do in catarrh, deafness results. 
This is relieved often suddenly, and with a crackling 
sound when the tube is opened, so that the air can pass 
through. The act of swallowing opens the tube. In 
blowing the nose, we can feel a pressure in the ears 
made by the air forced through these tubes. 

(c) The mouth. 

(d) The windpipe. 

(e) The gullet. 

The last two openings are at the bottom of the throat. 
The windpipe lies in front, and is usually open. The 
gullet is behind it, and is usually closed. 

The Larynx. 

9. The larynx, or voice-box, is on the top of the 
windpipe. It is made of cartilage, lined with mucous 
membrane. It forms a prominence in the throat which 
is called Adam's apple. It is divided into two chambers 
by a pair of curtains, whose edges are the vocal chords. 

10. The slit between the vocal chords is the glottis. 
It may be closed entirely or widely opened. When it is 
closed, breathing is stopped. 

The Windpipe. 

11. The windpipe (trachea) is four inches (10 c - m -) long. 
Most of the tubes in the body have soft walls, which 
fall together when the tube is empty. The gullet is 
such a tube ; but the windpipe has stiff walls that keep 
it always open. Its walls are made stiff by a series of 
sixteen to twenty rings, made of cartilage. These rings 



108 



UNION SERIES, NO. 3. 



are not complete, but are like a horseshoe in shape. They 
leave a space which is filled in with membrane. 

12. The reason for this construction is easily seen. 
The tube must be kept wide open, so that air can pass 
through. Food and blood, or other fluids, can force their 
way through soft tubes ; but it is necessary that the air 



Bronchial 
tubes. 



Larynx, 




should have a perfectly free course, so the windpipe 
and the bronchial tubes are made hard. 

13. But if the rings of cartilage completely surrounded 
the tube, they would press on the gullet which is be- 
hind it. Besides, it could not enlarge or contract at all. 
Because the back of the wall of the windpipe is soft, 



PHYSIOLOGY AND HEALTH. 109 

the gullet is not compressed, and the windpipe can be 
narrowed, bringing the ends of the cartilage together. 
This is done in speaking and singing. 

The Bronchi. 

14. The windpipe divides in the chest into two branches 
called bronchi, one of which goes to the right lung and 
the other to the left. These bronchi have also rings of 
cartilage in their walls. 

The Bronchial Tubes. 

15. Arriving at the lungs, the bronchi divide into 
the bronchial tubes, and these go throughout the lungs, 
constantly giving off branches. The smallest branches 
end in the lobules (bunches of air-sacs), which are not 
more than one-fiftieth of an inch (.5 mm -) wide. 

16. We may compare the windpipe to the trunk of 
a tree. The bronchi are two great branches, and the 
lobules containing the air-sacs are the leaves on the ends 
of the smallest twigs. 

Blood-Vessels of the Lungs. 

17. Having traced the passages by which the air is 
introduced, let us examine the blood-vessels of the lungs. 
The pulmonary artery comes from the right ventricle 
of the heart. It soon divides into two branches, which' 
enter the lungs with the bronchi. These branches 
divide and subdivide as the bronchial tubes do. On 
reaching the lobules and air-sacs, the capillary blood- 
vessels form a close net-work around them. From these 
net-works small veins come off, which keep uniting and 



110 



UNION SERIES, NO. 3. 



forming larger and larger veins as they pass out, until 
finally one or two large veins emerge from each lung at 
the point where the arteries and bronchi go in. All 
these tubes, lying close together, make the " root " of the 
lung. The pulmonary veins empty into the left auricle 
of the heart. 



Larynx. 




18. If we picture the air-passages as a tree, we can 
picture the blood-vessels as a vine following the branches 
of the tree out to the ends of the twigs. 

19. Besides the blood-vessels and air-tubes, there are 
in the lungs fibers, many of them elastic, which hold 
these parts together. 



PHYSIOLOGY AND HEALTH. Ill 

The Pleura. 

20. Each lung is covered by a bag made of a very 
delicate membrane, called the pleura. The lung is not 
contained in the bag; but the bag, which is closed, is 
wrapped about it, — one layer adhering closely to the 
lung, the other to the inside of the chest. The layers 
are kept moist and smooth and play on each other, so 
that in the movements of the lungs there is no fric- 
tion. The pleura performs the same service for the lung 
that the pericardium does for the heart. 

21. The pleura is sensitive, and when it becomes in- 
flamed is very painful. This condition is called pleurisy. 

22. The lungs are perfectly adapted to the purpose 
of bringing the blood and the air into close contact. 
Oxj^gen can readily pass through the wall of the air-sac 
and the wall of the capillary, both of which are thin- 
ner than the thinnest tissue-paper, and enter the blood. 
Carbon dioxide can as readily pass in the other direction. 

Ill 

Breathing. 

1. But the apparatus, thus far described, is not suffi- 
cient. The air-passages are open and air will enter. But 
it is necessary that the air in the lungs should be 
constantly renewed; that the old air should pass out, 
and the fresh air should go in, fifteen or twenty times 
in a minute. This is effected by breathing. 

2. Fifteen or twenty times in a minute, — tw T enty-five 
thousand times in a day, — we repeat this act while life 
continues. It is a voluntary act, and it is also an in- 



112 



UNION SERIES, NO. 3. 



voluntary act. We can breathe at will or we can hold 
our breath for a time, but not long. The demand of 
the body for air soon overcomes us, and we must breathe 
whether we will or not. 

3 . Breathing must go on during sleep and other tem- 
porary unconsciousness, and so it is made, like the beat- 
ing of the heart, independent of the will. 

4. To understand the act of breathing, we must ex- 
amine the chest and its muscles. 



The Chest. 



5. The chest is a bony cage which contains the heart 
and the lungs. It has the backbone behind, the breast- 
bone in front, and the ribs 
completing the circle. It has 
an opening at the top between 
the muscles of the neck. Its 
floor is formed by the dia- 
phragm. 

6. The diaphragm is a sheet 
of muscle and tendon attached 
to the backbone and the breast- 
bone, and to the edges of the 
lower ribs. It stretches across 
the cavity of the body, and 
divides the chest from the 
abdomen. 

7. On the outside of the 
chest are the respiratory muscles attached to the ribs and 
breast-bone. 

8. We have here a cage or box which is remarkable 




PHYSIOLOGY AND HEALTH. 113 

in this respect. It has walls of bone which afford pro- 
tection to the delicate organs which it contains, and yet 
it is capable of expansion and contraction. Thus the 
strength which belongs to hard material, like bone, is 
combined with the flexibility of a softer structure. 

9. Watch a person breathing, and you see what? 
You see the chest rise and enlarge, and then fall and 
contract. It does not enlarge because the air enters it. 
The opposite is true. The air enters because the chest 
enlarges. It is the principle of the bellows. Take hold of 
the handles and open the bellows, and the air rushes in. 
Close it, and the air is forced out. Air is always pressing 
in every direction, and will enter every vacant space 
which presents itself. 

10. The chest is expanded in the following way : The 
muscular diaphragm, which is not flat but arches up into 
the chest, contracts and descends, thus making the chest 
deeper. At the same time the external muscles act and 
draw the ribs and breast-bone, upward and outward. 
The lungs which are elastic, and are held to the chest- 
wall by the pleura, expand as the chest expands, and 
every little air-sac in them expands. The air pours into 
the cavity, thus enlarged, through the respiratory pas- 
sages. In an instant the muscles are relaxed. The 
diaphragm, forced up by the contents of the abdomen, 
arches into the chest and lessens its size. The ribs settle 
down and the chest narrows, and the elastic lungs, which 
have been stretched, contract, and the air is gently 
pressed out. In ordinary, quiet breathing, only certain 
small muscles of the chest are brought into play. But 
in hard breathing, as in asthma or croup, the larger 
muscles act with great force. 



114 UNION SERIES, NO. 8. 

IV 

Changes in the Blood. 

1. The blood that goes to the lungs from the right 
ventricle of the heart is purplish-red in color. The blood 
that comes from the lungs to the left auricle of the heart 
is scarlet in color. The scarlet blood, after reaching the 
left auricle, passes to the left ventricle and thence into the 
arteries that carry it through the body. It retains its 
scarlet color until it enters the capillaries in the tissues. 
There it turns purplish-red, and so continues during its 
course through the veins to the right auricle of the heart, 
thence into the right ventricle, and so on to the capil- 
laries of the lungs, where it again becomes scarlet. 

2. In the lungs oxygen enters the blood, and gives 
it the scarlet color. In the tissues oxygen is given up 
by the blood, and it loses its scarlet color. If a little 
dark blood from the veins be shaken up in the air, it 
will take up oxygen and turn scarlet. 

3. It has been found that the red corpuscles are the 
carriers of oxygen. They may be called the chariots in 
which the King of the Elements rides to his destination 
in the body. 

4. The carbon dioxide is taken up into the capillaries 
chiefly by the fluid portion of the blood. It is given 
off from the capillaries of the lungs. 

V 

Ventilation. 

1. To be healthful the air must be pure, — that is, it 
must contain the proper amount of oxygen and carbon 
dioxide, and it must be free from all injurious gases. 



PHYSIOLOGY AND HEALTH. 115 

2. Air that has been once breathed is impure, because 
it has lost oxygen and gained carbon dioxide and other 
impurities. Fires and lights make air impure. Nature 
preserves the purity of the air, as a whole, by keeping 
it in motion. The polluted air that hangs over a city is 
swept away, and replaced by winds from the great un- 
inhabited spaces. Nature ventilates for us out-of-doors 
on a grand scale. 

3. But we live most of the time indoors. We shut 
out the winds, because we must keep warm. To keep 
warm and have pure air to breathe is often very difficult, 
but we must have it in order to keep well. We should 
either open our windows and doors for a minute every 
little while, to let the bad air out and the pure air in, 
or we should have our rooms so arranged that pure air 
will keep coming in all the time, and bad air going out. 
One way of doing this, when nothing better is provided, 
is to fit a board a few inches wide underneath the lower 
sash of the window. This makes an opening between 
the two sashes across the middle of the window, where 
pure air may be continually coming in without causing 
a draft. 

4. In addition to this, there should be some way of 
escape for the bad air. For this purpose doors and win- 
dows should be opened frequently. While this is being 
done in a " living room," delicate persons and those liable 
to take cold may be protected by extra wraps, or they 
may go into another room. 

5. When a school-room is being thus aired the pupils 
should spend the time in vigorous exercise, to avoid 
taking cold. The heat should be turned on before and 
during such an airing, that the cold air coming in may 



116 UNION SERIES, NO. 3. 

be quickly warmed. Unless care is taken to prevent it 
the air in school-rooms, halls, parlors, work-shops, or any 
closed place occupied by a number of people, soon be- 
comes loaded with impurities. Every person in such a 
place is spoiling half a barrel of air with every breath 
he sends out. Pupils are often dull and have headaches, 
and audiences become inattentive from being poisoned 
with bad air. 

6. As soon as a school or audience is dismissed, all the 
windows and doors should be thrown wide open until 
the impure air is driven out. 

7. A person occupying a room alone should not remain 
in it long without a change of air. No person should 
sleep all night in a closed room, breathing over and 
over the air that is made more poisonous with every 
breath. 

8. Scientific men are constantly studying the question, 
How shall we secure good ventilation ? — and no perfect 
method has been devised. 

9. The nose is a good tester of the air of a room. 
When it smells close, it is impure. But after some time 
spent in a close room, the nose becomes accustomed to 
the bad air and is a less faithful monitor. A person 
coming from out-of-doors quickly detects impurities of 
the air, which may not be noticed by those inside. 

10. While the construction of school-rooms and other 
public buildings must be left to engineers and architects, 
those who have charge of such buildings must exercise 
constant vigilance to introduce fresh air. In our homes 
the same care must be taken. Sleeping-rooms should be 
thoroughly aired during the day, and for persons in good 
health an open window at night is desirable. 



PHYSIOLOGY AND HEALTH. 



117 



VT 



The Voice. 



1. The voice-box is situated in the top of the windpipe. 
Sound is made as the breath is going out, and not com- 
monly as it is passing in. In this box the air passes 
through a slit between the vocal 
chords. The vocal chords can be 
made tight or loose by little mus- 
cles connected with them ; and the 
opening between them (glottis) can 
be made narrow or wide. When 
the chords are tight and the slit is 
narrow, a high tone is produced. 
When the chords are loose and 
the opening is wide, a low tone is 
produced. The chords are set in 
vibration as the air passes between 
them, and sound is made just as it is in a music pipe. 

2. In a piped instrument, like an organ, there must be 
a pipe for each note. A single pipe, with a single pair of 
chords in the human throat, makes all the varied tones 
of the voice. This is effected by a change in the tension of 
the chords and the width of the glottis, and by changes 
in the width and length of the windpipe. 

3. Sounds are made in the voice-box. They are 
shaped into words, and are otherwise modified in the 
cavities of the throat and head and mouth. 

4. Voices differ in strength and quality. All voices 
can be improved bj^ cultivation. Distinctness of utter- 
ance is especially desirable. 




118 UNION SERIES, NO. S. 

5. American voices are justly criticized by Europeans 
as being too high-pitched and shrill. We should culti- 
vate the deeper tones as they do. 

VII 

Effects of Alcohol and Tobacco upon the Lungs. 

1. We have seen that alcohol paralyzes the r.erves in 
the walls of the small blood-vessels, causing them to ex- 
pand and hold more blood than they should. It affects 
in this way the blood-vessels in the lungs. The blood 
then does not properly circulate through these impor- 
tant breathing organs, and they become liable to disease. 
Persons who drink alcoholic liquors contract colds easily, 
because the mucous membrane of the throat and lungs 
is weakened by alcohol, and thus is more liable to in- 
flammation from slight causes. 

2. When alcohol is taken up by the blood, some of it 
soaks through the blood-vessels upon the delicate tissues 
of the lungs themselves, and injures them in proportion 
to the amount that reaches them and the frequency of its 
presence. It is a matter of common medical testimony 
that the use of alcohol is a fruitful cause of lung diseases. 

3. An eminent English physician, 1 who has had an 
extended connection with a hospital for consumptives in 
England, says that among the beer-drinkers is frequently 
found a general congestion of the small blood-vessels, — 
a tendency to hemorrhage, and a more or less thickened 
condition of lung tissue. And he adds that, "when 
such lungs break down, the secretion is more likely to 
be profuse, and the destruction rapid." 

1 R. E. Thompson, M. D., Senior Assistant Physician and Path- 
ologist to Brompton Hospital for Consumptives, 



PHYSIOLOG Y AND HEALTH. 110 

4. A form of consumption, resembling the consump- 
tion of beer-drinkers, is frequent among the free drinkers 
of wine. 1 Anything which lowers vitality, while at the 
same time it injures the lungs, is a predisposing cause of 
consumption. Medical men are discovering that alcohol 
is a cause of this disease. In the British army stationed 
at home, where the soldiers obtain alcoholic liquors with 
little or no restraint, the two most frequent causes of 
death are delirium tremens and consumption. One form 
of fatal lung disease is now called alcoholic consumption, 
because it is known to be caused by the use of alcohol. 
It has also been observed that the children of drinking 
parents often inherit a tendency to consumption. 

5. Tobacco, as well as alcoholic liquors, often produces 
a chronic catarrh of the throat and nose. 



ILLUSTRATIONS. 

1. Get from the druggist's a tumblerful of lime-water. With 
a glass-tube blow the breath through it, and it will become turbid 
by the union of carbon dioxide of the breath with the lime. 

2. Voice-box, windpipe, and lungs can easily be obtained from 
the butcher's. The structure of the tubes can be tested and their 
divisions. The light and cellular structure of the lung can be 
shown. 

3. A bellows illustrates well the action of breathing. 



QUESTIONS. 
I 

1. What bodily need is more pressing than the need of food and 
drink ? 

2. What is air? 

* Dr. Ac B. Palmer : Science and Practice of Medicine, page 294, 



120 UNION SERIES, NO. S. 

3. What act is constantly repeated through life? 

4. How much air do we take in with each breath ? What is the 
composition of air that is breathed out? 

5. How does expired air compare with inspired air in its 
composition ? 

6. What is the use of nitrogen in the air? 

7. What is the use of carbon dioxide in the air? 

8. State one point of difference between city air and country 
air. 

9. What is the place of oxygen among the chemical elements ? 

ii 

1. How do the lowest orders of animal life take in oxygen? 
Why may not the higher animals take it in the same way ? 

2, 3, How does the frog take in oxj'gen? How do fishes take 
in oxygen ? Why does a land animal need a different apparatus ? 

4. What are the lungs? 

5. Where do the respiratory passages begin? 

6. Does the mouth really belong to the respiratory passages? 
What reason for breathing through the nose rather than the 
mouth ? 

7. What is snoring? 

8. Describe the throat and the openings into and out from it. 

9. Describe the larynx ; the vocal chords. 

10. What is the glottis? 

11. Describe the windpipe. 

12. Why has it cartilage in its walls ? 

13. Why are the rings of cartilage incomplete ? 

14. What are the bronchi ? 

15. What are the bronchial tubes? 

16. To what may the windpipe and its branches be compared ? 

17. Trace the blood-vessels from the heart to the lungs and 
back. 

18. To what may the blood-vessels of the lungs be compared? 

19. What holds the vessels and air-tubes together? 

20. What is the pleura, and what is its use? 

21. What is pleurisy? 

22. Are the lungs well adapted to their purpose? 



PR YSIOL OGY AND HEALTH. 121 



in 

1, 2. What is the process of breathing and why is it necessary ? 

3. Can breathing be suspended at will? 

5. Describe the chest. 

6. Describe the diaphragm. 

7. What are the respiratory muscles? 

8. In what respect is the chest a remarkable box? 

9. 10. What makes the chest expand in breathing? What 
makes the air enter? What makes it go out? 

IV 

1. What color has the blood in the right side of the heart? in the 
left side of the heart? Where do the changes of color take place? 

2. What causes the changes of color? 

3. What is the work of the red corpuscles? 

4. What part of the blood takes up the most carbon dioxide? 
Where is carbon dioxide given off ? 

v 

1. What is pure air? 

2. What makes air impure ? How does nature preserve the 
purity of the air? 

3. 4. Why is it so difficult to secure pure air for breathing? 

5. What is a good test of the character of air? 

6. How should we try to secure pure air? 

VI 

1. Describe the voice-box. 

2. How can a single tube, with the voice-box, make so many 
different notes ? 

3. Where are sounds shaped into words? 

4. 5. What can you say of cultivation of the speaking voice? 

VII 

1. What effect has alcohol on the blood-vessels of the lungs ? 

2, 3. How does alcohol affect the substance of the lungs ? 

4, What disease of the lungs is caused by alcohol? 

5. What effect has tobacco on the throat and nose? 



122 



UNION SERIES, NO. 8. 




CHAPTER IX. 



BONES AND JOINTS. 

I 

1 , There is a vast num- 
ber of animals constituting 
the lower orders, and their 
bodies are composed of soft 
material only. They float 
in the water and the air, or 
they crawl upon the earth. 
Such are the infusoria, that 
the microscope reveals in 
a drop of water, and such 
are worms and larvae. 

2. But all higher ani- 
mals have a hard frame- 
work, to which the muscles 
and other soft parts are 
attached. This frame-work 
may be on the outside, and 
serve as a defense. This is 
the case in shell-fish and 
in turtles and snails, or it 
may be inside and covered 
with soft parts. This is 
the case in animals that 
have a backbone (verte- 
brates). 



PHYSIOLOGY AND HEALTH. 



123 



3. The substance which constitutes the frame-work of 
the human body- 
is called bone. 

4. Bone is hard 
and strong, and 
slightly elastic. 
In living bodies 
it is pink in color. 
Old, dead bones 
are white. 

5. Bone is made 
of mineral mat- 
ter and animal 
matter combined. 
If bone be put 
in the fire, the 
animal matter is 
burned out, and 
you have only the 
mineral matter 
remaining. But 
the form of the 
bone is preserved, although it is very brittle. If a bone 
is allowed to soak for ten days in a weak solution of 
hydrochloric acid (12 per cent.), the mineral matter will 
be dissolved, and only the animal matter will remain, 
preserving the form of the bone. A bone thus treated 
loses its hardness, and is so flexible that it may be tied 
in a knot. 

6. Mineral matter constitutes two-thirds of the bone 
of all living creatures. Animal matter constitutes one- 
third of the same, 




124 



UNION SERIES, NO. 3. 



Bone consists of, — parts in 100,— 




Phosphate of lime 


53 


Carbonate of lime 


11 


Other salts . 


3 


Animal matter 


33 




ToTAL 100 

7. Some of the bones are long, some are flat, and 
some are very irregular in shape. A long bone has a 

shaft which is com- 
paratively slender, 
and two ends that 
are enlarged. 

8. If you saw 
through the bone 
crosswise, and also 
lengthwise, you 
find that the shaft 
is very hard, but has a canal in it, while the end has only 
a thin layer of hard bone on the surface ; and within it 
is made of a kind of honeycomb of bone, with no central 
canal. The short and flat bones are made like the ends 
of the long bones, with layers of hard bone on the sur- 
face, and a honeycomb mass within. 

9. Take the thigh-bone {femur) as an illustration of 
a long bone. 
The shaft, on 
which thick 
muscles lie, 
is made slen- 
der to occupy 
as little room 
as may be. Its substance is very hard and compact to 




PHYSIOLOGY AND HEALTH. 



125 



give it strength The ends are expanded, because numer- 
ous muscles must find room for their attachments there, 
and because a large surface is needed for 
the joints. But these are all honeycombed 
within to make them lighter. 

10. It is a well-known principle, that 
a hollow shaft is stronger for support than a 
solid shaft of the same material and of the 
same weight. The construction of the bones 
is such as to combine strength and light- 
ness in a high degree. 

Formation and Growth of Bone. 

11. In the newborn infant none of the 
bones are fully formed. Its skeleton con- U\ 
sists in part of cartilage. This is gradually 
changed to bone. But the process is not 
completed until twenty-five or thirty years 
of age. In childhood the bone itself is less 
brittle than in later life. The skeleton of 
a child is accordingly much more flexible 
in its nature than that of a person of mature years. 

Uses of the Bones. 

12. The bony frame has two principal uses. First, 
it encloses and protects important organs. The chest 
contains the heart and lungs. The abdomen contains 
the stomach and other organs of digestion. These last 
are not wholly surrounded by bone, as the heart and 
lungs are. It is necessary that there should be freedom 
of motion at the waist, and therefore there is no bony 
wall in front. 



126 



UNION SERIES, NO. S. 




13. The skull is a tight box to hold the brain. The 
openings into and out of it are small, and its shape 

is such as to resist great pres- 
sure, or severe blows. The or- 
gans of special sense, — the eye, 
the ear, the nasal cavities, and 
the tongue, — are contained in 
the skull. 

14. From the cavity of the 
skull a canal goes down through 
the backbone, which lodges the 
spinal cord. The backbone is ex- 
ceedingly well adapted to hold 
and protect this principal organ. 
Strong, bony prominences stand 
out from it, and these are over- 
laid by muscular masses. Only great force can reach 
or disturb the spinal cord. The cord does not fill the 
canal, but hangs in the center of it, so that it is not 
liable to be pinched by the movements of the bones of 
which the spinal column is made. 

15. Besides protecting internal organs, the bony frame 
gives shape to the body ; it gives steady support to the 
soft parts, and enables us to stand and move as we could 
not do without it. 

16. There are two hundred bones in the body of an 
adult. Before the bones are completed, a single bone 
is often represented by two or three pieces, so that the 
number of bones in a child would be much greater. The 
six very small bones of the ears are not included in this 
number ; neither are the teeth, which are not true bones. 
The sesamoidal bones, found in the tendons, are not 
included. 



PHYSIOLOGY AND HEALTH. 



127 



The bones are classified as 


fol 


lows : — 




In the skull .... 


22 


In the spinal column . 


26 


fEibs . . 24 J 




In the trunk < Sternum . 1 > 


26 


I Hyoid . . 1 ) 




In the upper limbs 


64 


In the lower limbs 


62 



Total 



200 



17. The skull is composed of flat 
and irregular bones united by close 
and immovable joints. Most of the 
bones of the skull are in pairs. 

18. The spinal column is made of 
twenty-six distinct bones (vertebrae), 
quite odd in shape. Each has a cen- 
tral opening in it; and when they 
are united in a column, these open- 
ings make the canal which encloses 
the spinal cord. 

19. The spinal column is well 
fitted for its work. It must be very 
strong to support the weight often 
placed upon it. It must be capable 
of bending and twisting in different 
directions. It must have elasticity 
enough to break the force of jars 
sustained in jumping and running. 
This latter quality it has by reason 
of the cartilages interposed between 
the vertebrae, and also by reason of the 
curves in it. 




128 UNION SERIES, NO. 3. 

20. The spinal column is never perfectly straight; if 
it were, every step would jar the brain. It curves back 

between the shoulders and 
forward in the waist. Thus 
the skull is poised, not as on 
the top of a stiff rod, but as 
on a bent spring. 

21. But the head should 
be held erect. A round back, 
and a head bent forward, are 
marks of old age. All labor 
tends to bring them into that position, and when the 
muscles lose their elasticity it becomes fixed. 

22. Feeble health will cause stooping shoulders and 
a contracted chest. Indolent and careless habits may do 
the same thing. An effort should be made to cultivate 
an upright bearing in sitting or standing. It is more 
graceful and healthful. 

Curvature of the Spine. 

23. The spine sometimes curves to one side as well as 
forward. This occurs in delicate children, and is pro- 
moted by sitting sidewise at a desk with one arm on it 
and the shoulder raised, as in writing. When, after two 
or three hours of sitting, the head feels heavy and the 
body settles down into a bent position, a good run and 
some fresh air for ten minutes will straighten the spine. 

The Ribs. 

24. On each side there are twelve ribs, and they are 
joined to the backbone. Some of them are connected 



PHYSIOLOGY AND HEALTH, 



129 




in front with the breast-bone {sternum). These are called 
true ribs. Of the remaining five, called false ribs, three 
are joined with 
the ribs above 
them. The low- 
est two, known 
as floating ribs, 
are quite short, 
and are attach- 
ed only to the 
backbone. 

25. The costal cartilages connect the seven true ribs to 
the breast-bone. They connect each of the upper three 
false ribs to the ribs above ; and they form the tips of 
the two floating ribs. These cartilages are, in form and 
size, continuations of the ribs. Their substance is more 
flexible and elastic than bone. As the chest expands in 
breathing they twist outward, and by their recoil they 
contract the chest in expiration. 

26. Nature has given to the chest-walls a flexibility 
that adapts them wonderfully to the work of breathing. 
This flexibility at the same time makes it easy to press 
them out of shape. When any portion of the lung is 
gone, a depression soon appears in the chest-wall, and 
some diseases of the heart and lungs cause a bulging 
of the wall. Because there is no bony frame across the 
front of the body at the waist to resist pressure, a tight 
belt or tight clothing will press the waist out of shape. 
It is alike folly and sin to deliberately make a deformity 
by thus compressing the ribs with tight clothing. Such 
a course enfeebles the body by limiting the breathing 
powers, and by confining heart and stomach and liver 



130 



UNION SERIES, NO. 3. 



in too small a space. A small, tapering waist, squeezed 
out of its true proportion with the shoulders and hips, 
is no mark of beauty in the eyes of one of a cultivated 
taste. It is repulsive to an observer who has even a 
slight knowledge of the correct proportions of the human 
figure. 

A pinched waist is a self-inflicted deformity, an indi- 
cation of ignorance or a silly brain. 

The Upper Extremity, 

27. The shoulder-blade (scapula) and the collar-bone 
(clavicle) together make the shoulder. Notice that the 

shoulder-blade, while 
it lies upon the back, 
is not directly con- 
nected with the trunk. 

The collar-bone is joined to the breast-bone in front. 

Both these bones are joined to 

the chest-wall by strong muscles. 

The shoulder, while it is very 

firm, has given to it a very free 

movement. 

28, Observe the difference in 
this respect between the shoulder 
and the hip. The uses of the 
arm and hand make elasticity 
and free movement more desir- 
able than great strength. The 
uses of the lower limbs make 
strength and firmness the most 
needed qualities. The hip-bone 
is therefore directly united with the trunk by a close joint. 





PHYSIOLOGY AND HEALTH. 



131 



29. Between the shoulder and elbow is one large bone 
(humerus). Between the elbow and the hand are two 
slender bones (radius and ulna). The ra- 
dius is on the thumb side, and the ulna 
on the side of the little finger. The hand 
consists of carpus , metacarpus, and phalanges. 

Carpus. 

30. The carpus is made of eight little 
bones (carpal bones). At first it would 
seem as if they were crowded together at 
random, and might be of any shape. But 
a study of the wrist, and its movement, 
shows that each little bone is shaped with 

definite design ; and 
that the combination 
of the eight secures 
strength and firmness, with freedom 
of motion in all directions in a re- 
markable degree. 

31. The palm of the hand has 
« five (metacarpal) bones. These curve 
i§ slightly, so as to make a hollow in 

the hand. Ligaments and muscles 
bind them together. They can be 
felt in the back of the hand, but 
are well covered in front. 

32. The thumb and fingers have 
fourteen little bones, which are called phalanges, from 
a word meaning a line of soldiers, because they are 
arranged in order side by side. 





132 



UNION SERIES, NO. 3. 



The Lower Extremities. 

33. The hip-bones are large and strong, and so irreg- 
ular in shape, that the old anatomists who named the 
bones could think of no name which would describe 
them, so they called them the ossa innominata (unnamed) 




bones. These two bones, with the last two bones of the 
spinal column (sacrum and coccyx), make a cavity called 
the pelvis (basin). 

34. The pelvis encloses some of the internal organs, 
and at the same time it is an arch that supports the 
weight of the spinal column and the trunk, and trans- 
mits it to the bones of the legs. 

35. The thigh-bone (femur) is the largest and longest 
bone in the body. This bone, with the thick muscles 



PHYSIOLOGY AND HEALTH. 



133 




attached to it, has much to do with the strength and 
grace of movement in an upright posture. Monkeys 
and the lower tribes of men have short 
thigh-bones. In the higher orders of men 
they are longer. 

36. Between the knee and ankle are two 
bones (tibia and fibula). The tibia, or shin- 
bone, is next in length to the femur. 

37. The frame-work of the foot is similar 
to that of the hand. The hand has carpus, 
metacarpus, and phalanges. The foot has 
tarsus, metatarsus, and phalanges. In monk- 
eys the foot and hand are used for similar 

purposes, and do not differ as 
much in the details of their 
structure as they do in man. 
The human foot being de- 
signed solely for support and 
movement, the bones form an 
arch. This arch is the highest 
in the more highly developed 
races. The arch gives a spring to the step, 
and makes walking easy. Flat-footed per- 
! sons are not good pedestrians. 

38. Man is distinguished from the low r er 
animals by his erect position, and his dig- 
nified and graceful movements. The gait 
is an indication of character, and may con- 
tribute much to the expression of manly 
dignity and womanly beauty. It is surprising, there- 
fore, that civilized people should deliberately cripple the 
feet, so as to make ease and grace of motion impossible. 



134 



UNION SERIES, NO. 8. 



No woman can walk becomingly with a narrow French 
heel under the middle of her foot, and no man can step 

freely and smoothly with his 
toes crowded together by a 
narrow, tight boot. The feet 
of the majority of the Ameri- 
cans and Europeans of adult 
age are deformed. 

39. To secure a well-de- 
veloped figure, it is impor- 
tant to avoid awkward and 
cramped postures in sitting 
or standing. Free exercise 
of the muscles improves the 
shape. Narcotics and such 
like substances that poison 
the blood interfere with the 
growth of the bony frame-work. Boys who use tobacco 




are liable to be stunted. 



II 



The Joints. 

1. The bones which compose the skeleton are united 
by joints of different kinds. Each one is adapted to 
the needs of the part to which it belongs. 

2. In the skull, for example, motion between the bones 
is not necessary after birth. We have there immovable 
joints. The flat bones are firmly united by their edges, 
which are made with points, like the teeth of a saw, 
so that they can lock together. By middle life some 
of them have grown together, so that they cannot be 
separated. 



PHYSIOLOGY AND HEALTH. 



135 




3. Between the vertebrae that comprise the backbone 
are joints that have very slight motion. Their bony 
surfaces are united by 
cartilage that twists or 
yields a little. These, 
and a few others like 
them, are slightly mov- 
able joints. 

4. When we speak 
of joints in the body, 
we commonly think of 
those that are movable 
only. They are more 
numerous than fixed 
joints. 

Structure. — Parts Composing a Joint. 

5. The bones entering into them are covered with a 
thin layer of cartilage (gristle) 
that never changes into bone as 
some cartilages do. Its surface is 
very smooth. Bands of fibrous 
tissue, called ligaments, surround 
the joints and hold the bones to- 
gether. These are generally loose 
enough to allow some separation 
of the surfaces of the bones. They 
are not elastic. When a bone gets 
out of joint, it must break through 
the surrounding ligament. The 
proper way to restore a dislocated 

joint is to make the end of the bone pass through the 




136 



UNION SERIES, NO. 3. 






hole in the ligament by which it came out, This can 
often be done by a skillful person with very little force. 

6. A sprain is an injury by which the ligaments of 
a joint are torn and stretched. The ligaments are often 
helped to hold the bones in place by muscles which pass 
over the joints. 

7, Perhaps the most remarkable thing about a joint 
is its lining. The cavity between the bones is lined by 
a very thin membrane, called the synovial membrane. 
This membrane pours out the fluid that keeps the joints 
smooth. The joints of machinery need frequent oiling, 
to prevent them from rusting or wearing out too fast. 

The human joint must 
also be "oiled," and it 
makes an oil of its own. 
Just enough of this oil, 
or joint- water, is always 
found in the cavity to 
make the surfaces play 
together, without notice- 
able friction. 

8. Some of the joints 
are simply two flat sur- 
faces, which glide upon 
each other in different 
directions. Such are to 
be found in the carpus and tarsus. Some of the joints 
are like a hinge. The bones can move only backward 
and forward as a door does. The elbow is a hinge- 
joint. There are two ball-and-socket joints. These are 
the shoulder and the hip. They permit the limb to be 
moved about in every direction. 




PHYSIOLOG Y AND HEALTH. 137 

9. In early life the joints are very flexible, and per- 
mit of free and graceful movements. In old age they 
become stiff, and the movements of the limbs are slow 
and constrained. Rheumatism, and other diseases which 
affect the joints, make a young person feel and move like 
one who is infirm. 

Ill 

Effect of Alcohol on the Bones and Joints. 

1. Gout is a very painful and often a dangerous disease 
of the joints, induced by rich food and the use of alco- 
holic mixtures. Sometimes the disease is inherited from 
drinking parents by persons who have never used such 
drinks themselves. 

2. As alcohol is capable of hindering and impairing 
the development of any of the various tissues of the 
body, the bones," which are its frame-work, may suffer also 
from its use. It is conceded that it is the nature of 
tobacco, as well as alcohol, to stunt the development 
of the bony frame, and dwarf the growth of children 
and young persons who are foolish enough to use these 
poisonous substances. 

3. Youth is the period for growth and development. 
If growth is stunted during youth by the use of cider, 
beer, wine, tobacco, or by any other vicious habits, it 
cannot be afterwards made up. Stature and ability thus 
dwarfed will always be so much less then they might 
have been. 

4. Smoking, drinking, and other evil habits in youth, 
sometimes called " sowing wild oats/' reduce the power 
of enjoying the true pleasures of youth, and also yield 
a harvest of pain and loss in after years. 



138 UNION SERIES, NO. 3. 

ILLUSTRATIONS. 

1. Show a fresh bone and a dried bone. Get the boys to saw 
bones in various directions and investigate their internal structure. 
Soak a bone in a twelve per cent, solution of hydrochloric acid for 
a week to dissolve the animal matter. Burn a bone and show it 
as it appears when the amimal matter is removed. 

2. Obtain, if possible, specimens of all the bones described. 

3. Show the joints in the leg of a chicken or of a lamb. Point 
out the ligaments and cartilage. 



QUESTIONS. 
I 

1. What part of the animal kingdom is without bones or other 
hard frame-work? 

2. What two kinds of hard frame-work in animals ? 

3. 4, 5. Describe bone. 

6. What is its chemical composition? 

7. What shapes have the bones? 

8. What is the difference in structure between the shafts and 
the ends of long bones ? 

9. Illustrate by the thigh-bone. 

10. Why are the bones hollow? 

11. Is the skeleton of a newborn infant all bone? 

12. What are two principal uses of the skeleton? 

13. Describe the skull. 

14. Describe the spinal canal. 

15. Could we stand erect without the skeleton? 

16. How many bones are there in the body? How many in 
each part ? 

17. What kind of bones form the skull ? 

18. 19. What are the vertebrae ? How are they adapted to their 
purpose? 

20. Is the spinal column perfectly straight? 

21, 22. What causes stooping shoulders? 
23. What causes curvature of the spine? 



PHYSIOLOGY AND HEALTH. 139 

24. How many ribs have we? How are these classified? 

25. Describe the costal cartilages. 

26. What is the effect of tight clothing ? 

27. What bones constitute the shoulder? 

28. What difference between the shoulder and the hip? 

29. Where is the humerus? the radius and ulna? 

30. What is the carpus? 

31. What is the metacarpus? 

32. What are the phalanges ? 

33. Describe the hip-bones. 

34. W'hat is the pelvis? 

35. Describe the thigh-bone. 

36. Describe the tibia and fibula. 

37. Describe the frame-work of the foot, What is the difference 
between the frame-work of the feet and of the hands ? 

38. How are the feet often crippled? 

39. How may the figure be improved? 

ii 

1. How are the bones of the skeleton united? 

2. Where do we find immovable joints? 

3. What is the character of the joints between the vertebrae? 

4. Which are more numerous in the body — the movable or 
immovable joints? 

5. What are the parts composing a joint? 

6. What is a sprain? 

7. How are the joints kept smooth? 

8. Mention some of the different kinds of joints. 

9. What change takes place in the joints in old age? 

in 

1. What is gout, and how may it be caused? 

2. What effect may alcohol and tobacco have upon the bones? 

3. If the development of the body is checked in youth, can 
the loss be afterwards made up? 

4. What permanent harm results from " sowing wild oats " ? 



140 



UNION SERIES, NO. 3. 




PHYSIOLOGY AND HEALTH. 



141 



THE HUMAN SKELETON. 



Bones of the Head, Trunk, Legs, and Arms. 



Os frontis — Frontal bone. 

Parietal bone. 

Temporal bone. 

Coronal suture. 

Os mala; — Cheek-bone. 

Ossa nasi — Nasal bones. 

Superior maxillarv — Upper jaw-bone. 

Orbits. 

Side of os occipitis — Occipital bone. 

Condyloid process of lower jaw. 

Angle of lower jaw. 

Symphysis of lower jaw. 

Four lower cervical vertebrae (seven in 
all). 

Two upper and two lower dorsal verte- 
brae ^twelve in all). 

Lumbar vertebra; ^five in number). 

Os sacrum — False vertebrae. 

Os coccygis. 

Cartilages of ribs. 

Ribs. 

First bone of sternum, ) Rww% „* ^.^ 

Second bone of sternum, j breast-bones. 

Cartilago ensiformis. 

Clavicles — Collar-bones. 

Coracoid process of scapula — Shoulder 
blade. 

Acromion of scapula. 

Venter of scapula, anterior surface. 



27. Heads of os humeri — Arm-bone. 

28. Body of os humeri. 

29. Condyles of os humeri. 

30. Head' of radius — Outer bone of fore- 

arm. 

31. Body of radius. 

32. Ulna — Inner bone of fore-arm. 

33. Carpal ends of radius and ulna. 

34. Venter of ilium. 

35. Anterior superior process of ilium. 

36. Anterior inferior process of ilium. 

37. Symphysis of pubis. 

38. Tuberosity of ischium. 

39. Brim of pelvis. 

40. Foramen ovale. 

41. Head of os f emoris — Femur of thigh- 

bone. 

42. Neck of os femoris. 

43. Trochanter major of os femoris. 

44. Body of os femoris. 

45. Condyles of os femoris. 

46. Patells — Knee-pan. 

47. Head of tibia — Thick bone on ante- 

rior and inner side of leg. 

48. Body of tibia. 

49. Base of tibia. 

50. Fibula — Thin bone on external side 

of leg. 



Front View of Right Hand and Wrist. 



1. Scaphoid bone. 

2. Semilunar bone. 

3. Cuneiform bone. 

4. Pisiform bone. 

5. Os trapesium. 

6. Os trapezoides. 

7. Os magnum. 

8. Unciform bone. 



9. Metacarpal bones of thumb and fin- 
gers. 

10. First row of phalanges of thumb and 

fingers. 

11. Second row of phalanges of fingers. 

12. Third row of phalanges of thumb and 

fingers. 



Front View of Right Foot. 



1. Superior articulated surface of astra- 

galus. 

2. Anterior portion of astragalus. 

3. Os calcis — Heel-bone. 

4. Commencement of groove of interos- 

seous ligament. 

5. Scaphoid bone. 

6. Tuberosity of scaphoid bone. 



7. Internal cuneiform bone. 

8. Middle cuneiform bone. 

9. External cuneiform bone. 

10. Cuboid bone. 

11. Metatarsal bones. 

12. First row of phalanges of toes. 

13. Second row of phalanges. 

14. Third row of phalanges. 



142 UNION SERIES, NO. S. 



CHAPTER X. 



MOTION. 



1. One thing that distinguishes animals from plants 
is, that they have the power of motion at will. Plants 
and non-living objects move only when they are acted 
upon by some force outside of themselves. There is a 
force residing in the animal body which enables it to 
move itself, and to impart motion to other objects. 

2 . The power of motion does not belong to all organs 
of the body, but principally to the muscles. Bones cannot 
move themselves, neither can ligaments nor nerves nor 
fat. There are, however, besides the muscles, two other 
elements of the body that can move. 

3 . By watching the white corpuscles of the blood with 
a microscope, it has been found that they can move. 
They are round bodies and have no organs of motion, 
but they have a way of their own of traveling. 

4. Some part of their surface bulges out and con- 
tinues to swell, until the whole globule has gone into 
the swelling, and so has changed its position a little. If 
now another swelling appears in the same side, and the 
globule goes into it in the same way, it will have moved 
a little further, and so on indefinitely. 

5. Again, if the lining of the breathing passages be 
carefully observed with a powerful microscope, it will 



PHYSIOLOGY AND HEALTH. 143 

be seen to be overspread by what appears like a crop 
of wheat in the field. Numberless little stems stand up- 
right as the stalks of wheat do, and they are all moving 
as the wheat moves when a breeze blows over it. It is 
a waving motion, — a quick stroke in one direction and 
then a slow movement back again, like the strokes of a 
broom when one is sweeping the floor. Indeed, that is 
what these waving stems are doing. They are sweep- 
ing the dust, w^hich comes in with the breath, and the 
phlegm which gathers in the bronchial tubes, up towards 
the mouth. The quick stroke is always in that direction ; 
the return is slow. 

6. These little stems are like fine hairs, and therefore 
they are called cilia (cilium, a hair). They are not mus- 
cles, but they have the power of moving as muscles do. 

7. These cilia are found not only in the breathing 
passages, but in some other tubes in the body. Their 
work always is to keep the fluid that moistens the lining 
of the tubes in motion in one direction. 

8. The muscles are the chief organs of motion, and 
there are two kinds, — 

Voluntary Muscles. Involuntary Muscles. 

The Voluntary Muscles. 

9. The voluntary muscles cover the bones, and are 
attached to them. For that reason they are sometimes 
called skeletal muscles. They give a rounded and grace- 
ful outline to the body. 

10. Muscle is lean meat. The roasting-piece of beef 
and the slice of steak are muscle. If you should ex- 
amine the flesh of the animal after the skin has been 
removed, you would find that the lean meat on the limb 



144 



UNION SERIES, NO. S. 




or in the trunk is made up of bundles of flesh, each 
enclosed in a sheet of tough, stringy, white tissue, and 
joined by threads of this same white tissue (connective 
tissue) to other bundles. This structure can easily be 

seen in any slice of meat cut 
" across the grain." There 
are large bundles, and they 
are made of smaller bundles. 
The smallest bundles of all 
are made of muscle-fibers. 

11. These fibers can be 
discerned only with the mi- 
roscope. They measure not 
more than one-four-hundredth of an inch (OS 111111111 -) across. 
It is in them that the power of motion resides. 

12. When seen under a microscope the fibers of vol- 
untary muscles have lines running across them, and are 
thereby known as 
striped muscles. 

13. The muscle 
moves and makes 
other things also 
move, by growing 
shorter and thick- 
er. This is most 
readily noticed in 
the biceps-muscle 
of the arm. When 
we desire to bend 

the elbow, this muscle swells and shortens, the arm- 
bone to which it is attached is drawn up, and the hand 
approaches the shoulder. 




PHYSIOLOGY AND HEALTH. 145 

14. All the voluntary muscles are attached to the 
bones — most of them to two bones. As a muscle short- 
ens, one of these bones is drawn toward the other. So 
all the movements of body and limbs are produced. 

15. The muscles act upon the bones as upon levers. 
Sometimes it is the short arm of the lever that is acted 
upon. A swift motion of the long arm is the result. 
Sometimes the long arm is acted upon. A slow but 
powerful movement of the short arm is the result. 
Sometimes one end of the bone is fixed, and the muscle 
is attached at the other end, or in the middle of the 
bone. 

16. Muscles are of various sizes and shapes. Some 
are flat, and some are round. Some are short, and 
some are long. The longest is a ribbon-like muscle in 
the thigh, called the sartorius (tailor's muscle), which 




may be tw r o feet long. The shortest is a little muscle of 
the ear which is not more than one quarter of an inch 
in length. 

17. Most of the voluntary muscles end in tendons, by 
which they are attached to the bones. Tendons are what 
we know as the " cords " in the body. You can see and 
feel them in your wrist; when the muscle of the fore-arm 
contracts and doubles the fist, the cords stand out. When 
there is not much fat over the muscles the tendons show 
very plainly. The largest and strongest tendon in the 



146 



UNION SERIES, NO. S. 



body is the tendon of Achilles, 1 which attaches the great 
muscle of the calf of the leg to the heel. 

18. There are more than five hundred 
muscles in the body, and every muscle has 
been named by the anatomists. But nearly 
all the muscles are in pairs, the two sides 
of the body being exactly alike. 

19. A muscle seldom acts alone. Several 
muscles are grouped together to make a 
certain movement. Different groups are 
opposed to each other in action. For ex- 
ample, the muscles on the front of the arm 
that bend the joints are opposed by the mus- 
cles on the back of the arm that straighten 
the joints. By the continued action of vari- 
ous opposing groups, all the movements of 
the body are effected. Some simple acts, 
— walking, for instance, — involve many 
muscles and very complicated movements. 



* 



/i 



The Involuntary Muscles. 



20. The black spot in the center of the 

. -^ eye, which is called the pupil, is sometimes 

large and sometimes small. When the light 
is strong, it is small. In dim light it grows large. By 
shading with your hand some one's eye, and then remov- 
ing the hand suddenly, you can see the change taking 



1 The legend relates that Thetis, the mother of Achilles, dipped 
him, while an infant, into the waters of the Styx, making him 
invulnerable, except where her fingers held him by this tendon. 
He was finally slain by an arrow which wounded him in this spot. 



PHYSIOLOGY AND HEALTH. 147 

place. The pupil is a hole in the iris. The iris, — the 
colored part of the eyeball, — is a membrane made in 
part of muscle-fibers. These fibers run in different direc- 
tions. Part of them surround the pupil in rings, and 
part of them run from the edge of the pupil straight out 
like the spokes of a wheel. When the circular fibers con- 
tract, it makes the pupil small. When the straight fibers 
■ contract, it makes the pupil large, 

21. But you cannot make these fibers contract by your 
will alone. If you will to move your hand or your leg, 
it moves instantly. In some way your will can make 
these muscles contract. They are voluntary muscles ; 
but you may will as earnestly as you please to have the 
pupil of the eye grow larger or smaller, it does not 
change in this way. These muscle-fibers will not obey 
your will. They are involuntary. If you changfe your 
position, so that a brighter light will fall on your eye, 
they will act at once. 

22. The iris is the best example of involuntary 
muscle to be seen on the outside of the body. But the 
movements of all the organs within the body are made 
by involuntary muscle-fibers. They are found in the 
wall of the alimentary canal, in the bronchial tubes, in 
the heart, in the blood-vessels and lymphatics, and in 
every internal organ which has the power of motion. 

23. In this way Nature not only relieves us of the 
burden of maintaining these movements of the vital 
organs, by exercise of the will ; she also withholds from 
us the power of checking or stopping them at will. 

24. The involuntary muscles are different in structure 
from the voluntary muscles. The fiber of striped volun- 
tary muscle has already been described. The fiber of 



148 



UNION SERIES, NO. 3. 



in voluntas muscle is shaped like a spindle and pointed 
at both ends. The fibers of voluntary muscles are joined 
in bundles, like the strands in a rope. The fibers of in- 
voluntary muscles are joined by their ends, which lap 
over each other, and they are either scattered through 
the tissue in which they are, as in the skin, or they form 
sheets of muscle, as in the wall of 
the alimentary canal. They are not 
attached to bones like the voluntary 
muscles. 

25 . The involuntary muscles differ 
from the voluntary in their mode 
of action. The voluntary muscles 
act very quickly. It does not take 
more than one-tenth of a second for 
a voluntary muscle to contract after 
the will determines it. The invol- 
untary muscles act slowly. 

26. The muscle of the heart is 
involuntarj 7 . We have no direct con- 
trol over its action, but it differs in 
structure from the general voluntary 

and involuntary muscles. The heart muscle-fiber is very 
fine, — it is striped, — it branches and connects with neigh- 
boring fibers. 

Muscular Exercise. 

27, Our life can manifest itself only through muscular 
action. The man whose muscles are all paralyzed can 
hold no communication with the outer world either by 
gesture, speech, or glance. The greater part of the daily 
work of the world is done by the muscles. But among 




PHYSIOLOGY AND HEALTH. 149 

civilized men the brain plays so prominent a part that 
the muscular system does not get proper consideration. 
The heroes of the primitive races are the strong and 
agile of body. The heroes of cultivated races are the 
mentally vigorous and learned. 

28. We need to take care that the muscles get regu- 
lar exercise. A cultivated mind in a strong body has an 
advantage over the same mind in a weak body; and 
no part of the body can be neglected without crippling 
to some extent the rest. 

29. Use makes the muscles grow in size and firmness. 
An arm or leg which has been broken and kept in splints 
always shrinks in size, because it is not used. 

30. It is not important to have very large muscles. 
Great strength is useful only in a few occupations, but it 
is very desirable to have the muscles firm and active and 
well-proportioned. 

31. For those who are sitting much of the time, and 
for those whose work is chiefly brain-work, muscular 
exercise is rest. Rest is not always gained by ceasing 
from work. The tired brain-worker often lies awake for 
hours after retiring, the brain refusing to be still and the 
muscular system restless and uncomfortable. A walk of 
a mile, or exercise for half an hour with dumb-bells, will 
draw the blood from the brain and give the muscles their 
needed refreshment, and insure the wished-for sleep. 

32. Muscular exercise makes the blood flow more 
swiftly through all the tissues, removing waste matter 
and giving oxygen. 

33. Muscular exercise should be taken regularly. One 
who exercises only occasionally, as inclination urges, will 
not get as much profit or enjoyment from it as one who 
exercises for some time every day. 



150 UNION SERIES, NO. S. 

34. Exercise that is taken with pleasure is very much 
better than enforced exercise. Children and all young 
animals, even the fiercest, play a great deal. Exercise 
is especially needful for them because they are growing, 
and so Nature implants in them a love for play which 
keeps them active. It is well that children should be 
instructed in useful work that gives them exercise. But 
nothing should be allowed to deprive a child of all 
opportunity for play. 

35. Exercise taken in the open air is more beneficial, 
both in summer and winter, than in-door exercise. Part 
of the good got from it is due to the oxygen of the air. 

36. Do not exercise too long or too violently. Young 
people sometimes do themselves severe injury, when 
spurred by ambition to exert themselves too much in 
this way. 

37. Violent exercise should not be taken immediately 
before or immediately after eating. It draws the blood 
from the stomach at a time when it is needed there. 
Dyspepsia is often caused in this way. 

38. Girls need exercise as well as boys. It is a mis- 
take to check their natural impulse to it through false 
ideas of propriety. They should rather be encouraged to 
take exercise. It is unfortunate that the dress of women 
is such as to hinder free movement. 

39. Girls who are fond of open-air exercise, who run 
and take part in vigorous out-door games, usually grow 
to a more healthy and vigorous womanhood than those 
who do not. Walking, lawn tennis, archery, and croquet 
are good forms of out-door exercise for girls who have 
outgrown childish plays. But no one can ever outgrow 
the necessity for spending some time each day in some 



PHYSIOLOGY AND HEALTH. 151 

active exercise in the open air, for which we should plan 
as regularly as for our meals. The health necessary to 
usefulness, enjoyment, and beauty is soon lost by shutting 
one's self up in the house. 

IV 

Alcohol and the Muscles. 

1. The strength of a muscle consists in its power of 
contraction, — that is, its power to swell and grow shorter, 
thus moving itself and other things. Alcohol reduces 
this contractile power. " A moderate dose of beer or wine 
will, in most cases, at once diminish the utmost weight 
which a healthy person can lift." 1 

2. Muscle becomes exhausted by exercise sooner when 
an alcoholic drink has been taken than when it has not. 
The workman who takes beer or wine to strengthen him, 
or " brace him up," as he says, cannot endure so long a 
strain of hard work as one can who does not take these 
drinks. Neither will his muscles be steady and precise 
enough to do fine work. The shaking hand and un- 
steady nerves of the habitual drinker are not the only 
proofs that alcohol injures the muscles. A champion 
English rower once refused to take a doctor's prescription 
of w r ine, by saying that he should not win his race if he 
did. He explained that in order to win, an oarsman 
must have precision, decision, presence of mind, and 
endurance, and these he cannot have if he takes alcohol. 2 

1 Dr. William Brunton. 

2 This oarsman gave as an illustration of his belief an account 
of a race he once rowed with another oarsman fully as compe- 
tent as himself, and who at the start had some slight advantage 



152 UNION SERIES, NO. 3. 

3. A famous oarsman says, that in his opinion the 
best physical performances can only be secured through 
absolute abstinence from the use of alcohol and tobacco. 

4. Alcohol is very likely to cause a fatty degeneration 
of the muscles. The blood being improperly purified, 
carries about with it little particles of fat, which are 
deposited between the minute muscular fibers. When 
this fat gathers in large quantities, it crowds upon the 
muscular fibers and interferes with their action. 

5. Sometimes, instead of this deposit of fat between 
the muscular fibers, or together with it, there is a gradual 
change of the lean muscle itself into fat. This is called 
fatty degeneration, and is liable to occur in the heart, 
liver, kidneys, arteries, and other parts of the body, as 
well as in the voluntary muscles. 

6. Tobacco contains a poison, nicotine, which has 
special power for causing relaxation of muscles. Its chief 
action is upon the heart and brain, but the muscles are 
so affected by it that they soon lose their steadiness and 
precision. A drawing teacher of large experience says 

over him. But the other oarsman took a drink of whisky just 
as he stepped into his boat, while the one who related the story 
took none. When they had gone a little way the stroke of the one 
who had taken the whisky began to loose its precision ; he al- 
lowed his attention to be diverted by the cheers of the spectators; 
he was not able to decide quickly as to the best course when they 
met with an obstacle, and before the goal was reached he began to 
flag. The other did not flag and won the race. Yet when he set 
out he was not feeling well, and had to take the side of the river 
that gave him the sun in his face all the way. His victory, he 
firmly believed, was due to the sip of whisky his opponent took 
in starting, while he kept his head clear and muscles steady by 
not taking any. 



PHYSIOLOGY AND HEALTH. 153 

he can readily detect the boy who uses tobacco by his 
inability to draw a clean, straight line. 

7. Tobacco and alcohol are enemies to good muscles, 
and those who never use them have the best chance of 
winning in the race of life. 



ILLUSTRATIONS. 

1. A piece of raw meat shows the structure of muscle. Tear 
out the fibers of a muscle with needles, and examine them with a 
power of three or four hundred diameters. 

2. Illustrate the action of the muscles on the bones by using 
a ruler or a cane as a lever, and showing the different points at 
which the power and the fulcrum may be located. 



QUESTIONS. 

I 

1. What is one of the most obvious distinctions between plants 
and animals? 

2. In what parts of the body does the power of motion chiefly 
reside ? 

3. 4. Describe the movement of the white corpuscles of the 
blood. 

5, 6. Describe the cilia and their movement. 

7. What is the work of the cilia ? 

8. What two kinds of muscles are there? 

9. Where are the voluntary muscles placed? 

10. Describe a voluntary muscle. 

11. 12. Describe a voluntary muscle-fiber. 

13. How does muscle move and cause movement? 

14. To what are the voluntary muscles attached? 

15. How do muscles act on the bones? 



154 UNION SERIES, NO. 3. 

16. Are muscles uniform in size and shape? Which is the 
longest muscle in the body? Which is the shortest muscle in 
the body? 

17. What are tendons ? Where is the tendon of Achilles ? 

18. How many muscles are there in the body? How many 
pairs of muscles are there in the body ? 

19. How do muscles combine in action? 

20. What is the pupil of the eye ? What is the iris ? What 
makes the pupil dilate? What makes it contract? 

21. What kind of muscle is in the iris ? 

22. Where else are similar fibers found? 

23. Why are some muscles involuntary? 

24. Describe the involuntary muscle-fiber. 

25. What difference in action between voluntary and involun- 
tary muscles? 

26. What kind of muscle-fiber is found in the heart? 

27. What part do the muscles play in our lives? Why are 
the muscles neglected among highly civilized men? 

28. Does a strong body help the mind? 

29. What is the natural effect of exercise on the muscles? 

30. Is it important to have large muscles ? What qualities are 
desirable in the muscles? 

31. Is rest always gained by ceasing from work? How may 
exercise be rest? 

32. What effect has muscular exercise on the circulation? 

33. 34. How should exercise be taken in order to get the most 
profit from it? 

Why does Nature make children love play ? 

35, 36, 37. Name some important conditions to be observed in 
taking exercise. 

38, 39. Do girls need exercise as much as boys? Is exercise 
necessary for children only? 



IV 

1. What effect has alcohol on the contractile power of muscle ? 

2, 3. Will the muscles endure longer when alcoholic drinks are 
used? 



PHYSIOLOGY AND HEALTH. 155 

What effect has alcohol on the steadiness and precision of mus- 
cular action? 

4, 5. What change in muscle-fiber is caused by alcohol ? What 
tissues besides the muscles may be changed by alcohol? 

6. What effect has nicotine on the muscles? 

7. Who have the best chance of winning in the race for life ? 



156 



UNION SERIES, NO. 3. 



2 r u/.S 




UNION SERIES, NO. 3. 



157 



MUSCLES OF THE HUMAN BODY. 



Side View of Full Figure. 



Occipito-frontalis — Used to raise the 
eyebrows, etc. 

Temporalis — Helps to elevate the 
lower jaw. 

Orbicularis palpebrarm — Closes the 
eyelids. 

Ma'sseter — Helps to elevate the lower 
jaw, etc. 

Sterno-cleido-mastoiedeus — Moves the 
head forward, etc. 

Trapezius — Moves the head backward, 
sideways, etc. 

Platvsma niyoids — Assists in depress- 
ing- the angle of the mouth. 

Deltoides — Raises the arm, etc. 

Biceps flexor cubiti, ) Act together on 

Brachialis anticus, ] the fore-arm. 

Triceps extensor cubiti. 

Supinator radii longus — A flexor of 
the fore-arm. 

Extensor muscles of thumb. 

Extensor muscles of wrist. 

Fectoralis major, ) Lower the arm 

Latissimus dorsi, j when elevated, etc. 

Serratus magnus — Assists in advanc- 
ing the scapula, etc. 

Obliquus externus ) G ,,,,__ v4 . «.„ i 
nhdnminis. (Support the ab- 



abdominis, 
Rectus abdominis, 



dominal viscera. 



Gluteus medius, |f c * a* t e r nately 

Gluteus maximus, ^on the thigh-bone 
' J and pelvis. 

Tensor vaginae f emoris — Renders the 
fascia tense, etc. 

Vastus externus — Contributes to ex- 
tend the leg upon the thigh. 

Biceps flexor cruris — Assists in bend- 
ing the leg on the thigh, etc. 

Gastrocnemius — Forms the calf of 
the leg, etc. 

Tibialis anticus — With 31 bends foot 
on the leg, etc. 

Extensor communis digitorum — Aids 
in extending the toes, etc. 

Soleus. See 25. 

Peromeus longus, } f ct . together in 

Peronaeus brevis, j ^ m % the foot 

Peronaeus tertius — Flexor of the foot 

on the leg, etc. 
Abductor minimi digiti — Bends the 

little toe, etc. 
Extensor pollicis proprius — Extensor 

of great toe. 
Flexor communis digitorum — Bends 

the toes, etc. 
Tendo Achilles — Junction of 25 and 

26 



Front View of Right Arm. 



Deltoides. See 8 above. 
Pectoralis major. See 15 above. 
Coraco-brachialis — Assists to move 

arm backward and forward. 
Biceps flexor cubiti. See 9 above. 
Brachialis internns. See 10 above. 
Triceps extensor cubiti. See 11 above. 
Pronator radii teres — Turns palm of 

hand downward, etc. 
Supinator radii longus — Turns palm 

upward, etc. 
Flexor carpi radialis — Bends the wrist, 

etc. 



10. Palmaris longus, with fascia — Bends 

the hand, etc. 

11. Flexor digitorum communis — Bends 

fingers toward the palm, etc. 

12. Flexor carpi ulnaris — Bends the wrist, 

etc. 

13. Abductor pollicis manus — Carries the 

thumb outward, etc. 

14. Flexor brevis pollicis — Flexor of first 

joint of thumb. 

15. Palmaris brevis — A small muscle con- 

nected with little finger. 



Front View of Right Leg*. 



Gluteus medius. See 20 above. 

Tensor vaginae femoris. See 22 above. 

Psoas and iliacus — Bend the thing on 
pelvis, etc. 

Pectineus — Contributes to bend thigh- 
bone, etc. 

Abductor longus — One of the abduc- 
tors of thigh. 

Sartorius — Bends leg upon the thigh. 

Gracilis — Acts along with abductor 
muscles of thigh. 

Vastus internus, ) to ' 



11. Biceps flexor cruris. See 24 above. 

12. Insertion of ligament of patella into 

tibia. 

13. Tibialis anticus. See 26 above. 

14. Extensor communis digitorum. See 

27 above. 

15. Peronaeus longus. See 29 above. 

16. Gastrocnemius. See 25 above. 

17. Solaeus. See 28 above. 

18. Peronaeus brevis. See 30 above. 

19. Abductor pollicis pedis — Abductor of 

great toe. 



158 UNION SERIES, NO. 3. 



CHAPTER XI. 



THE NERVOUS SYSTEM. 



1. The human body is made of many members. Each 
member, — heart, stomach, lung, muscle, — has its own 
kind of work to do ; but each must act in harmony with 
all the rest. It is like a country with many states, cities, 
towns, and villages, each having its own affairs, but 
each dependent on the others and combining with them 
in national life. 

2. In order that they may so combine it is necessary, 
first, that they should have free communication and 
sympathy ; and secondly, that there should be a general 
government. 

3. The nervous system is the apparatus which brings 
the organs of the body into close communication with 
one another, and presides over and directs their action. 
The brain, the highest part of the nervous system, is the 
special seat of the mind. 

The Nerves. 

4. In dissecting the body of any animal, in nearly 
all the tissues are seen delicate white threads which are 
called nerves. If one of these threads be followed up, 
it will be found uniting with other threads ; and the 
bundle, so formed, uniting with other bundles, until at 



PHYSIOLOGY AND HEALTH. 



159 



•-Cerebrum. 
"Cerebellum. 



Spinal cord 




160 



UNION SERIES, NO. 3. 




last many have become joined in one large cord, which 

maj r be traced into the spinal cord in the backbone, or 

into the brain. 

5. Or starting from the brain and spinal cord, we find 

fortj^-three pairs of large white cords passing out through 
small openings in the skull and the back- 
bone, and soon dividing into branches, 
each of which divides again and again 
until the little white threads are spread 
through all the tissues. 



The Brain and Spinal Cord. 

6. The brain and spinal cord are called 
^\ nerve-centers. The brain is contained 

in the skull. It has about the consistency 
of new r cheese, and weighs in a grown 
man about three pounds (1361 & Tms -). 

7. The human brain is heavier than 
that of any other animal, except the ele- 
phant and whale. The elephant's brain 
weighs ten pounds (4536 grms -), the whale's 
five pounds (2268 g rms -). In proportion 
to the w T eight of the wdiole body, the 
brain of man is much heavier than that 
of either of these large animals. 

8. The spinal cord in man weighs 
about an ounce and one-half (42.5 s rms -), 
one thirty-second of the weight of the 

brain. In the lower animals the cord is larger in pro- 
portion to the brain, and in some of the lowest of the 
animals, with backbones, the spinal cord is actually 
heavier than the brain. The brain is made up of several 





PHYSIOLOGY AND HEALTH. 



161 



parts easily distinguished. A deep furrow, running for- 
ward and backward, divides it into halves, which are 
alike. The brain is therefore a double organ. 

9. In man, the largest of its parts are the two hemi- 
spheres of the cerebrum or upper part of the brain, and 
these fill the vault 
of the skull. In the 
lower animals, the 
hemispheres are 
relatively smaller. 
In the ape and in 
domestic animals, 
they approach in 
size to the human. 
In fishes, which are 
the least i n telligent 
of all the lower ani- 
mals with a back- 
bone (vertebrates), 
they are quite 
small. Since in the animal world greater intelligence is 
always to be found associated with larger hemispheres, 
and since in man the hemispheres greatly surpass those 
of any other animal, it is inferred that the hemispheres 
are the seat of those higher powers of mind which dis- 
tinguish mankind from the brute creation. 

10. If the hemispheres of the brain be examined by 
dissection, they are found to consist of matter of differ- 
ent shades of color. On the surface is a layer of grayish 
matter about one-eighth of an inch (3 m - m ) deep. Beneath 
this, and forming the mass of the organ, is white matter. 
The white matter is made up of nerve-threads running 




162 



UNION SERIES, NO. 3. 





in different directions, connecting the different portions 
of the brain with each other and with the spinal cord. 
The gray matter consists principally of cells, in which 
the work of the brain is done. The amount of 
gray matter which a brain contains is an in- 
dex of the work that it can do. In the higher 
animals, and especially in man, nature has a 
way of increasing the working portion of the 
brain without increasing the size of the whole. 
The surface of such brains, instead of being 
smooth, is thrown into folds, called convo- 
lutions, with furrows about an inch deep be- 
tween them. The gray surface, being carried 
down into these furrows, is very much in- 
creased in extent. In the lower animals no 
such furrows are found; but in the higher 
animals, such as the horse and dog, they are 
BraiTof a Fish, very marked. In mankind they are more 
numerous and much deeper then in any other animal. 

11. The characteristics which particularly distinguish 
the human brain from that of the brain of all the lower 
animals are its absolute size, — the relative size of the 
hemispheres, — and the number of the convolutions and 
depth of the furrows between them. 

12. A large and well-proportioned head is a good, but 
not an infallible index of a superior brain. For the size 
of the brain does not absolutely determine the extent of 
brain surface, or the amount of brain power. Not only 
may the convolutions be more numerous in the smaller 
brain, but the quality may be superior. Mental power 
depends on the quality as well as on the quantity of 
gray matter. 



PHYSIOLOGY AND HEALTH. 163 

13. The spinal cord extends down from the base of 
the brain through the spinal canal. From its sides come 
off at regular intervals the large, white nerve cords, 
which issue in pairs from the spinal canal on opposite 
sides, and send their branches to all parts of the body. 

14. The cord does not fill the canal, but hangs loosely 
in it. For this reason it is not likely to be pressed and 
twisted, as the backbone is bent and turned. If in any 
way one of the bones called vertebra, which make up 
the backbone, is put out of joint, it presses on the cord 
and causes paralysis of the body below. But these bones 
are very firmly joined, and this accident seldom happens. 

15. Cut across a spinal cord, and you find it looks like 
a cut brain. It has gray and white matter, but the gray 
matter is in the center and not on the surface. The spinal 
cord connects the brain with the nerves. It also does an 
independent work which we will notice further on. 

16. Each nerve is a bundle of nerve-threads, called 
fibers, and each of these fibers connects a point in the 
surface with a cell in the spinal cord. 

Work of the Nerves. 

17. The nerves are in some respects like telegraph 
wires, — they are conductors. If you touch a red-hot 
stove, the impression made upon the end of the nerve 
in your finger is carried up to the brain, and in some 
of the cells of the gray matter a sensation of pain is 
awakened. If you cut that nerve, you may hold your 
finger in the flame and have no sensation. 

18. Again, the nerve which ends in the muscle of your 
arm carries the message from your brain, when you wish 



164 UNION SERIES, NO. 3. 

the muscles to contract. If you cut that nerve the 
muscle no longer obeys your will. 

19. If a man has fallen on his head, and driven one of 
the vertebrae out of joint, so that the cord is compressed, 
he has neither feeling nor power of motion in the parts 
below the injury, because the course of the nerves w r hich 
convey sensation inward and messages outward is inter- 
rupted. 

20. Perception of external objects and voluntary mo- 
tion depend upon the nerves. Though the muscles are 
uninjured, and all other bodily organs perfect, if the 
nerves are rendered inactive, the body is helpless and 
senseless. 

Work of the Spinal Cord. 

21. The spinal cord is not only a conductor of im- 
pulses to and from the brain. It is a kind of lieutenant 
for the brain, and relieves it of much labor. Many of our 
movements are unconscious. We move about in sleep. 
When the spinal cord is injured, so that communication 
between the limbs and the brain is broken, the limbs 
can be made to move by tickling the feet. A frog whose 
head has been cut off will scratch his side, if a little 
acetic acid is dropped on it. 

22. These facts lead us to suppose that many bodily 
movements are made under the control of the spinal 
cord, the brain having only a general supervision. 

23. We determine, for example, to walk to school. 
This is a resolve of the brain, which at once sets the 
muscles into action to accomplish its purpose. When 
we are out on the familiar street, w r e move without 
any effort of the brain. Indeed, we may be conversing 



PHYSIOLOGY AND HEALTH. 165 

studying, or thinking, as we move along, and scarcely 
conscious of what we are doing. Meantime the spinal 
cord, the second in command, is presiding over all the 
complex muscular contractions that are required to carry 
us, leaving the brain free. 

24. One who is beginning to play on the pianoforte 
must give close attention, and strike each note with care. 
The brain must direct the playing. An expert player 
will run rapidly through difficult passages while engaged 
in conversation. The spinal cord has become trained, 
by long practice, to do much of what at first was done by 
the brain. 

25. Many of the lower animals are much superior to 
us in the use of their muscles. Their movements are 
more rapid and precise. Their spinal cords are larger 
in proportion to their brains. 

26. If the brain were obliged to direct all the pro- 
cesses of life, and all the complex movements of the 
muscles, it would have neither time nor energy for its 
higher work. 

27. The spinal cord has no sensation. All sensation, 
all consciousness, and all thought has its seat in the brain. 

28. The nervous system will endure much. It is said 
that one-fifth of the blood of the body is in the brain. 
It is, therefore, well nourished. In starvation the brain 
and nerves are the last of the tissues to waste. But the 
nervous system is frequently abused. Tired and aching 
brains, weak and irritable nerves, and the condition 
known as nervous prostration are much more common 
than they should be. Since all the processes of the body 
depend on the nerves, all are deranged when the nervous 
system is out of order. Stomach, heart, and lungs are 



166 UNION SERIES, NO. 3. 

affected. The feelings are perverted; the judgment and 
disposition are warped. 

Sleep. 

29. A great safeguard of the nervous system is sleep. 
Several hours in each twenty-four must be spent in 
sleep. An infant under six weeks of age sleeps most 
of the time. Children should sleep from eight to twelve 
hours. For adults seven or eight is sufficient. No one 
can endure absolute loss of sleep for many days; but 
many people take less sleep each night than they need. 
The result is, in a short time, exhaustion of the nervous 
system, and perhaps inability to fall asleep when they 
desire to do so. 

Exercise. 

30. Another safeguard of the nervous system is muscu- 
lar exercise. Those who are engaged in outdoor manual 
labor seldom have nervous exhaustion. It is a disease of 
brain- workers, and of those whose occupation involves 
much care and worry, and of those who have no steady 
occupation. Exercise in the open air is an antidote. 

What Injures the Nervous System. 

31. The nervous system may be injured by over-use. 
The number of hours of study or other brain-work that 
can be performed with safety any day varies greatly for 
different persons. But each should learn his own limits 
and not exceed them. Nature gives warning of danger 
by headache and languor and nervousness when we are 
going too far. Young persons, when preparing for exam- 
ination or competing for prizes, are sometimes stimulated 



PH YSIOL OGY AND HE A LTH. 167 

to do for weeks excessive brain-work, with insufficient 
sleep and exercise, — unconscious of the risk they run. 
Insanity has in some cases resulted. Worry is also more 
wearing than work. But worry is often a sign of over- 
work. The healthy brain will be undisturbed when the 
unhealthy one will be agitated by slight causes. 

32. Over-excitement is a more common cause of nerv- 
ous disorder than overwork, and the love for excitement 
grows with its gratification. It may be sought in read- 
ing sensational literature, in amusements, or society. In 
any case constant excitement is unhealthy, and begets 
exhaustion. 

II 

Effects of Alcohol, Tobacco, and other Narcotics. 

1. The use of poisonous drugs, such as alcohol and 
tobacco, is one of the most fruitful causes of nervous 
disease. 

2. We have seen that whenever alcohol is taken into 
the human system it quickly enters the blood, but does 
not become a part of the blood as food does. It is still 
alcohol, and a large part of it flows with the blood to 
the nerves and brain, where it soaks through the walls 
of the blood-vessels upon nerve and brain tissue itself. 
Nerve substance, which has been touched by alcohol, 
is at once deadened or paralyzed in proportion to the 
amount of alcohol reaching it. 

3. AVe have seen that when an alcoholic liquor has 
been taken the heart begins to beat more rapidly, because 
its inhibitory nerve that should check its too rapid beats 
is paralyzed, and it then sends more blood than it should 
send to the brain. At the same time the blood-vessels 



168 UNION SERIES, NO. 3. 

expand too much, because the nerves in their walls that 
should enable them to contract enough to prevent too 
much blood flowing through them are paralyzed. Thus, 
both checks that nature has provided to keep the right 
amount of blood in the right places are taken off by 
alcohol. By far too much blood then rushes to the head. 
It is a law of physiology that an increase in the amount 
of blood in any organ of the body increases the activity of 
that organ. Therefore, when the blood begins to rush 
into the brain the brain is at once excited. It may then 
act more rapidly than before ; but it is evident to an 
observer that this increased activity is not trustworthy. 1 

Alcohol Injures the Judgment. 

4. An important work of the brain is to consider 
whether the suggestions the mind receives are right or 
wrong, whether they are wise or unwise. This faculty 
of the brain, which is called judgment, is impaired by 
alcohol in proportion to the amount taken. A man's 
words may be more rapid and his imagination more 
active after he has taken wine, but he has not as good 
control over his thoughts. His imagination is likely to 

1 Sir Andrew Clark, one of the leading medical men of London, 
England, afid physician to Queen Victoria, says : " Every man 
who comes to the front of his profession in London is marked by 
this one characteristic, the more busy he gets the less in the shape 
of alcohol he takes, and his excuse is, ' I cannot take it and do my 
work.' " 

Another eminent English medical man says : " All alcohol and 
all things of an alcoholic nature injure the nerve tissue pro tem- 
pore, if not altogether. You may quicken the operations, but you 
do not improve them." 



PHYSIOLOGY AND HEALTH. 169 

lead him to make statements that are not true. At such 
times he indulges in foolish remarks; he is often quick to 
take offense, and worse still, makes himself disagreeable 
to those about him, because his power of discrimination 
and his sense of propriety are diminished. 

Alcohol Weakens the Will. 

5, When the judgment has concluded as to the right 
or wrong, the wisdom or folly of a suggested act, the 
mind then decides what shall be done. This power of 
the mind which decides and guides action is called the 
Will. One of the worst effects of alcohol upon the mind 
is its power to weaken and finally destroy the will. The 
poor drunkard, in his sober moments, stung with pain 
over the ruin his intemperance has brought to himself 
and his family, often determines that he will drink no 
more ; but under the power of appetite his weakened 
will yields to temptation, because it is not strong enough 
to carry out his good resolution. The time when a man 
could stop drinking, if he would, may be followed sooner 
than he thinks by the time when he would stop drinking 
if he could. This is because it is the nature of alcohol to 
weaken the will that should control the appetite, while 
at the same time it increases the appetite, making it more 
imperious and hence more difficult to control. 

6. When wine, or any other alcoholic liquor, causes 
the drinker to lose control of his limbs and stagger as 
he walks, it is not because the alcohol " has gone to his 
legs," as is often said, but because it has deadened that 
part of his brain that has control over the action of 
walking. 



170 UNION SERIES, NO. 3. 

7. All the changes in the brain caused by alcoholic 
drinks tend to become permanent with each repetition 
of the potion. There is a thickening and hardening of 
the substance of the brain which greatly injures the mind 
of the drinker. 1 " The deleterious influence of alcohol on 
the mental is not less marked than on the physical 
powers. The perceptions are blunted, the intellectual and 
moral faculties progressively deteriorate, until, at length, 
the confirmed inebriate, miserably depraved in body and 
brutalized in mind, has but one object in life, — namely, 
to gratify the morbid craving for alcohol." 2 

The Inheritance from Alcoholic Drinks. 

8. It is a well-known fact that children often inherit 
resemblances, likes and dislikes, and other characteris- 
tics of their parents. Thus, a drinking parent often be- 
queathes to his innocent child an appetite for strong 
drink. The injurious effects of alcohol upon the brain 
and nerves of the drinking parent often reappear in 
his children, affecting their character and physical con- 
ditions. Idiocy, insanity, w^eak minds, weak nerves, or 
nervous systems liable to give way under any unusual 
pressure, — perverted moral natures and vicious instincts, 
which may manifest themselves in various ways, are all 
results often inherited from the use of alcohol by parents. 

9. The evils inherited from the indulgence of alcoholic 
drinks are not confined to the children of drunkards only, 

1 Hyatt, the great Austrian anatomist, used to say that he could 
distinguish in the dissecting-room, in the darkest night, by one 
stroke of his scalpel, the brain of the dead inebriate from that of 
one who had lived a sober life. 

2 Dr. Austin Flint. 



PHYSIOLOGY AND HEALTH. 173 

lli What distinguishes the human brain from that of the 
lower animals? 

12. Is a large head a sure sign of an able brain? 

13. Where is the spinal cord situated? 

14. Does the spinal cord fill the canal? What is the conse- 
quence of getting a vertebrae out of joint? 

15. What is the appearance of a section of the spinal cord? 

16. What is a nerve made of? 

17. 18. What is the work of the nerves? 

19. Why are sensation and motion lost below an injury of the 
cord? 

20. What is the condition of a person whose nerves are incapa- 
ble of action ? 

21. What is the spinal cord besides being a conductor of im- 
pulses ? 

22. 23, 24. Show how the spinal cord presides over certain 
movements. 

25. In what point are the lower animals superior to us? 

26. What advantage in having the cord take part of the work of 
direction ? 

27. Has the cord sensations and consciousness ? 

28. Is the nervous system easily disordered? What is the result 
of disease of the nervous system ? 

29. How much time should be spent in sleep ? 

30. Name two safeguards of the nervous system. 

31. How may the nerves be injured ? 

32. What is the effect of constant excitement? 

II 

1. What are the effects of alcohol and similar poisons on the 
nervous system? 

2. How does alcohol reach the nerve centers ? 

3. How is the activity of the brain increased by alcohol ? 

4. 5, 6. How does alcohol affect the judgment? the will? the gait? 

7. What permanent change does alcohol make in the brain? 

8, 9. What inheritance may a drinking parent leave children? 
10, 11, 12. What effect is tobacco likely to have on a boy who 

uses it? 



174 UNION SERIES, NO. 3. 



CHAPTER XII 



THE SKIN. -BODILY HEAT. 



1. The skin is not only a covering for the outer 
parts of the body ; it is also an active organ, and has 
an important part in the processes of life. 

2. As a covering it is soft, pliable, and strong. It fits 
the form perfectly, and in health it never feels tight. 
It is fine in texture and beautiful in hue. 

3. The lower animals, whose skins are covered with 
hair or feathers, are sufficiently warm without further 
protection. But man has a more delicate skin. Its 
nerves are more susceptible, especially among civilized 
races, and therefore he procures clothing for himself. 

4. The skin is from one-fiftieth to one-eighth of an 
inch (.5 to .3 m - m -) in thickness, being thickest in the palms 
of the hands and soles of the feet, and other parts 
exposed to pressure. 

5. It may be divided into two laj r ers. The upper 
layer is called the epidermis or cuticle. The deeper 
layer is the true skin or dermis. The surface of the 
cuticle consists of dry, fine scales which are constantly 
coming off, as the deeper and growing portion pushes 
up. The cuticle has no blood-vessels or nerves in it. 
This makes it a better covering, as it is insensible to 
slight cuts, blows, and scratches. 



PHYSIOLOGY AND HEALTH. 



175 



The Hair. 

6. The hair is an outgrowth of the skin. Some of 
the tiny cells which form the deep layer of the cuticle, 
instead of being changed into dry, 
hard scales, are changed into hairs. 
Hairs are found all over the human 
skin, but on the larger part of it they 
are very short. 

The Nails. 

7. The nails are also a modifi- 
cation of the skin. These hard, 
smooth plates give firmness to the 
ends of the toes and fingers, and 
enable us to handle a small object 
better than we could without them. 

8. It is in the deep layer of the 
cuticle that the coloring matter, 
which makes some skins black and 
others dark, in various shades, is 
deposited. 

9. While the cuticle is without 
nerves or blood-vessels, the true skin 
or dermis is richly supplied with 
both. In a blister one or more layers 
of the cuticle are raised by water, 
which is gathered beneath it. If 
the whole cuticle is rubbed off, thei| 
dermis is uncovered, and looks raw 
and is extremely sensitive. 

10. In a healthy skin the blood in the deep layer 




176 



UNION SERIES, NO. 3. 



shows through the cuticle, giving it a rosy tint. In 

sickness, when the blood is scanty or is ill-supplied with 

red corpuscles, the skin looks 
pale and sallow. It is the life 
manifest in a healthy circu- 
lation that gives the bright 
and rosy tints, which make 
the skin beautiful. 

11. On the palms and in 
other places fine ridges, lying 
parallel and running in dif- 
ferent directions, can be seen 
by close looking. These are 
made of rows of little points, 
called papillse, which rise from 
the surface of the dermis and 
show through the cuticle. The 

papillse contain blood-vessels, and the ends of the nerves 

of touch or feeling. 

The Skin a Sense Organ. 

12. The skin is a most important organ of sensation. 
From the delicate nerve endings, which are spread all 
through it, messages of vari- 
ous kinds are carried to the 
brain. There are the nerves 
of feeling, by which pleas- 
ant or painful sensations are 
experienced. There are the 
nerves of touch, which are 
more numerous and sensitive in some places — the finger- 
ends for example, — than in others. There are the nerves 





PHYSIOLOGY AND HEALTH. 



177 



by which we appreciate the differences in the temperature 
of objects touched. There are the nerves which enable 
us to measure the pressure with which any thing rests 
upon them. 

13. These nerves are constantly bringing in from 
the skin information, abundant and various, as to objects 




around us. They tell us of their size, consistency, tem- 
perature, and weight. The information of objects, which 
we gain through the eye, must be aided and modified 
by the assistance of touch. It would be a greater mis- 
fortune to lose the sensitiveness of the skin than to lose 
our eye-sight or hearing. 



II 



Bodily Heat. 



1. Besides its use as a protection to the tissues beneath 
it and as an organ of sense, the skin has a very important 
office as a regulator of the heat of the body. 

2. One of the most remarkable powers of the liv- 
ing body is the power of maintaining in itself a certain 



178 UNWN SERIES, NO. 8. 

uniform temperature. 1 It is, with very rare exceptions, 
warmer than the air around, and it makes its own heat. 

3. If the bulb of a little fever thermometer, such as 
physicians carry, be placed in the mouth of a well man, 
and held there for five minutes, it will always mark 
between 97 and 99 degrees Fahrenheit (36.1 to 37.2 C). 
These will be the limits in summer and winter, in the 
tropics and in the arctic regions. If the bulb of the 
thermometer could be placed in the current of the blood, 
the mercury would rise a little higher. It would reach 
about 100 degrees Fahr. (37.7 C). 

4. The body, like every other material thing, has a 
tendency towards the temperature of the objects around 
it. If it is colder than the air, or than the walls or floor 
of the room, or than the stove in which a fire is burning, 
it receives heat. If it is warmer than these things, it 
loses heat. 2 

5. As has already been said, the temperature of the 
body is commonly several degrees above that of the air. 
In the winter we keep our rooms at 70 degrees Fahr. 
(21 C), which is thirty degrees less than the temperature 
of the blood. In the heats of summer the temperature of 
the air rarely reaches 100 degrees Fahr. (37.7 C). It may 



1 When Lieutenant Greely was rescued after a winter of expos- 
ure to an average temperature of 5 degrees Fahr. ( — 15 C), in a 
state of starvation, the thermometer indicated that his bodily heat 
was only about a degree Fahr. below the standard. 

2 A dead body seems to be much colder than surrounding 
objects. To the touch it is like a frozen thing. In reality it is 
no colder than the air of the room, or the bed on which it lies. 
Because it is so much colder than the living flesh, with which 
we unconsciously compare it, we think it colder than it is. 



PHYSIOLOGY AND HEALTH. 179 

be said, therefore, that the human body is constantly in 
an atmosphere which is colder than itself. 

6. The same is true of all animals. Cold-blooded 
animals, like fishes and frogs, are so called, not because 
their blood is cold, but because its temperature varies 
with that of the atmosphere, or the fluid in which they 
are. It is two or three degrees warmer than the sur- 
rounding medium. The blood of a snake in a hot sun 
may be much warmer than the human blood. The same 
animal in an atmosphere of 32 degrees Fahr. (0. C.) 
would have an internal temperature of 35 degrees or 36 
degrees (1.6 to 2.2 C.) only. 

7. The human body, then, is constantly losing heat 
by radiation, conduction, and convection. Since it main- 
tains a uniform temperature it must have a source of 
heat in itself. 

8. The three chief sources of heat are the sun, friction, 
and chemical action. The heat of the body is not directly 
derived from the sun. Friction of the blood and other 
moving fluids produces a little heat, but chemical action 
is by far the most effective cause of animal heat. When 
coal or wood is burned in the air, the phenomenon is 
called combustion. Oxygen unites with the carbon or 
other elements in the wood or coal, and light and heat 
are manifest. A slow combustion is going on all the 
time in the animal body. It is not active enough to 
make light, but it makes heat. The food that we eat 
may be likened to the fuel — the wood or the coal. The 
oxygen required is introduced by the breathing appara- 
tus, and is carried by the blood to all the tissues. Com- 
bustion cannot go on in the body without oxygen, as a 
fire cannot burn without a draught. As a wood or coal 



180 UNION SERIES, NO. 3. 

fire makes ashes, so the combustion that is going on in 
the body makes waste material which must be carried 
away by the blood, and thrown out by the lungs, skin, 
and kidneys. 

9. The body, therefore, is in some respects like a stove 
or a steam-engine, in which a constant combustion is 
going on. When this combustion stops the body is dead, 
and as long as it continues heat is produced. 

Clothing. 

10. Except in very hot climates the body would lose 
its heat to the cool air faster than it made it, if we did 
not take some means to make up for the loss. Our cloth- 
ing does not make us warm of itself, but it keeps what 
warmth we have in the body. The colder the outside 
air the thicker one's garments must be, not to keep out 
cold but to keep in heat. Some kinds of cloth are bet- 
ter for this purpose than others. Because wool is not so 
good a conductor of heat as cotton, a light woolen gar- 
ment is warmer than a cotton one of greater thickness. 
Linen is suitable for our dress in hot weather, because it 
is a good conductor of heat and allows it to pass off from 
the body more rapidly than a woolen garment of the 
same weight. Fur and feathers are very bad conductors 
of heat. They are accordingly given to the birds and 
beasts to answer the purpose of clothing. 

11. Outside of the tropics men require fires in winter 
to help to maintain their bodily heat. When we are 
chilled it is agreeable to warm ourselves by a hot fire ; 
but ordinarily the use of the fire is not to warm us, but 
to keep the temperature of our rooms such that we shall 



PHYSIOLOGY AND HEALTH. 181 

not lose heat too fast. From 65 to 70 degrees Fahr. 
(18.3 to 21.1 C.) is about right. In winter we eat more 
than in summer, and in winter w r e take more active 
exercise. By both these means our internal combustion 
is increased, and we produce more heat. 

The Skin a Regulator of Bodily Heat. 

12. The skin has in it very many blood-vessels. Cold 
makes them contract, and so drives the blood into the in- 
terior of the body where it is kept warm, the skin helping 
to retain the heat. 

13. When the surrounding air is very warm, it affects 
the blood-vessels in the opposite way. These vessels en- 
large, and the blood flows to them from the interior. 
Here, being near the air, it is rapidly cooled. It goes 
back to the interior to receive more heat, and to carry 
it to the skin and there again lose it to the air. 

The Sweat Glands. 

14. But there is another way in which the skin acts 
as a regulator of bodily heat, namely, through the sweat- 
glands. Over the whole surface are little openings called 
pores. There are two or three million of them in all, 
and in a square inch from five hundred to two thousand 
according to location. 

15. By examining carefully with a strong magnifying 
glass the ridges in the skin of the fingers, the openings of 
the pores can be seen. There is a row of them in each 
ridge, the pores being at equal distances apart. 

16. These pores are the mouths of the tubes. Following 



182 



UNION SERIES, NO. 3. 




one of them downward we should find that it takes a 
spiral course through the cuticle, it then passes directly 

through the dermis and terminates 
in a coil just underneath the skin. 
This coil is the sweat-gland. On 
its surface is a net-work of cap- 
illary blood-vessels. From these 
the sweat-gland draws fluid, from 
which it makes the perspiration 
that passes through the tube and 
appears on the surface.' 

17, In health the sweat-glands 
are always active; but ordinarily 
the fluid evaporates, as soon as it 
issues from the pores, and we do 
not see it. If the weather is very 
warm, or if we are exercising violently, perspiration flows 
more rapidly, and we see the drops standing over the 
pores, and they even run down in streams. The gentle 
perspiration, which is constant on a healthy skin, keeps 
it soft and pliable. If perspiration is stopped, the skin 
becomes dry and hard. 

18. It is a well-known fact that when water evaporates 
it cools everything around it. In the change from the 
liquid state to the state of vapor heat is taken up. Per- 
spiration evaporating takes heat from the skin. When 
the air about us is w r arm, or when our bodies are very 
warm from exercise, the blood flows to the skin and the 
heat of the body is reduced. When the surrounding air 
is cold, the blood-vessels of the skin contract, — there is 
less perspiration and less evaporation. 

19. The skin, with its sweat-glands, is an automatic, 



PHYSIOLOGY AND HEALTH. 



183 



regulating apparatus for the heat of the body. And so 
perfect is its working, that the internal heat is scarcely 
affected by the temperature of the air. Workmen have 
been known to enter a room in which the floor was red- 
hot, and the thermometer stood at 350 degrees Fahr. 
(176.6 C.) without harm. Chabert, a traveling showman, 
used to subject himself to a temperature of 400 to 600 
degrees Fahr. (205 to 315 C). This was possible only 
by reason of an enormous flow of perspiration, whose 
evaporation prevented overheating. 

Sebaceous Glands. 

20. Besides the sweat-glands, the skin has sebaceous 
glands. Most of these are close by the root of a hair, 
and open into the little pit from which 
the hair comes. They discharge an oily 
matter. None of them are to be found 
in the palms of the hands or soles of the 
feet; they would make them too slippery. 
In other places, they serve to make the 
skin smooth and soft. 

Muscle-Fibers in the Skin. 

21. Fibers of involuntary muscle are 
scattered through the skin. When cold 
air, or a sprinkling of cold water strikes 
the skin, it makes these fibers contract, 
causing the appearance which we call 
goose-flesh. The hair-sacs to w T hich the muscle-fibers 
are attached are pulled toward the surface, making little 
pin-head prominences. 




184 UNION SERIES, NO. 3. 

22. It is plain that an organ which has such impor- 
tant work to do as the skin has should be well cared for. 



Bathing. 

23. Bathing is of great importance. Not the hands 
and face only, but the whole body should be frequently 
washed. While the watery part of the perspiration evap- 
orates, the solid matter dissolved in it remains in the 
clothing and on the surface of the body. A dirty skin is 
quite likely to be an unhealthy skin. The pores should 
be kept open. 

24. Not only for cleanliness is bathing valuable, but 
to maintain the vigor of the skin. It is full of nerves 
and blood-vessels and muscle-fibers. The stimulating 
effect of water, and the rubbing that accompanies the 
bath, keep these in good working order. 

Colds. 

25. A cold is generally the result of chilling the 
surface of the body. A draught strikes it, or the feet 
get wet, and sickness results. We spend much of our 
time in warm rooms, and the skin, covered by thick cloth- 
ing, becomes tender. It cannot resist exposure. Those 
who are constantly in the open air take cold less fre- 
quently than those who live indoors. A daily morning 
bath in cool water invigorates the skin, and is a great 
protection against colds and catarrhs. The temperature 
of the water should be different for different persons. 
Those who are full-blooded and robust can use quite cold 
water and enjoy it. Those who are delicate must have 



PHYSIOLOGY AND HEALTH. 185 

tepid water. A bath should always be followed by a 
warm glow. 

26. For those whose health will not permit a daily 
bath, a " dry bath " is an excellent substitute. This con- 
sists in a vigorous rubbing of the skin with a towel or 
brush. 

27. The skin may be rendered unduly sensitive by 
too much protection. If the clothing worn is too thick, 
it keeps the skin too moist and debilitates it. Fur sacks 
are dangerous, because they overheat the skin if kept on 
in a warm room, and in going out into the cold air, with 
the blood-vessels of the skin full and the pores open, a 
chill and a cold are likely to follow. 

28. One who has a sore throat or sensitive lungs does 
well to wear a scarf, but a healthy person should leave 
the neck exposed in ordinary weather. 

Effects of Alcohol on the Skin. 

29. The skin usually becomes flushed very soon after 
an alcoholic drink has been taken, because, as we have 
seen, alcohol paralyzes the nerves in the walls of the 
blood-vessels, letting them stretch and hold an undue 
quantity of blood. The blood coming from the interior 
is warmer than the surface of the body, and as it rushes 
into the many blood-vessels of the skin a feeling of in- 
creased warmth is produced. The drinker thinks the 
alcohol has warmed him up. The truth is it is cooling 
him instead, because a larger quantity of blood than 
usual is near the surface of his body, where it is more 
rapidly cooled than in the warm, inner parts of the body. 
The colder the air the more quickly is this blood cooled. 



186 UNION SERIES, NO. 3. 

The man, therefore, who takes a "gin sling," or some 
other alcoholic mixture, when he is going out in cold 

weather, is making the worst possible preparation for 
withstanding the cold. If he deadens his senses with 
alcohol to such an extent that he is not conscious of 
feeling cold, he is in a still more dangerous condition, 
for he will then be apt to neglect to properly protect 
himself. Travelers in frozen regions have found alcohol 
worse than useless as a protection against cold. They 
have found also that men who have weakened their con- 
stitutions, by previous use of either alcohol or tobacco, 
are less able to endure the severe weather than those who 
have never used these things. 

30. Diseased conditions of the skin often result from 
the use of alcoholic drinks. As we have seen, alcohol 
injures the circulation of the blood, therefore the skin 
is not properly nourished and breaks up into dry scales 
which may stop up the pores. Unsightly blotches appear 
on the skin. The drunkard's red, swollen nose is often 
called a " rum-blossom," because, as is well known, alcohol 
is the cause of its enlargement. 



ILLUSTRATIONS. 

1. Eefer to the common example of the effect of exercise and' 
friction on the temperature and appearance of the skin. Wet a 
finger and hold it in a current of air, to note the cooling effect 
of evaporation. Refer to the apparent difference to the touch in 
the temperature of articles in the room, and explain this apparent 
difference as due to the differing power of conduction of heat in 
these substances. An oil-cloth seems colder than a carpet. Apply 
this principle to clothing. 



PHYSIOLOGY AND HEALTH. 187 

QUESTIONS. 

I 

1, 2, 3, 4. What two uses has the skin ? What kind of a covering 
is the skin? How thick is the skin? 

5, Into what two layers may it be divided? 

6, 7. What is hair? What are the nails? 

8, In what portion of the skin is its coloring matter found? 

9, 10, 11. What portion of the skin has blood-vessels and nerves ? 
What is a blister? What is the cause of the ruddy or pallid 
appearance of the skin? What makes the little ridges seen on 
the skin of the palm ? 

12, What do we learn of things around us through the skin ? 

13, How is the information carried to the brain? 

II 

1. Mention a third use of the skin. 

2, 3. What is the temperature of the interior of the body ? 

4. What determines the temperature of not-living objects? Does 
the body gain or lose heat in the same way as they do? 

5, 6. What relation has the temperature of the body to that of 
the air? Are the lower animals like man in this respect? 

7, 8, 9. Since the body is constantly losing heat, how is its tem- 
perature maintained? What are the three chief sources of heat? 
What is the source of the heat of the body? 

10, 11, Does clothing make the body warm ? What kinds of 
clothing are the best? Do fires make the body warm? 

12, 13, 14, 15. How do the blood-vessels of the skin regulate 
bodily heat? How many pores are there in the skin? 

16, 17, 18. What are the pores ? Describe a sweat-gland and its 
action. How is the skin cooled by the perspiration? 

19. Illustrate the action of the skin as a regulator of heat. 

20. What are the sebaceous glands, and what is their use? 

21. What muscle-fibers are there in the skin? 

22. 23, 24, 25, 26, Why is bathing important? Why is a morning 
bath a good preventive of cold? W T hat is a "dry bath"? 

27, 28. How may too much clothing do injury ? 

29, Does a drink of alcoholic liquor help any one to keep warm? 

30. What permanent effect may alcohol have on the skin? 



188 UNION SERIES, NO. 8. 



CHAPTER XIII. 



THE SENSES. -THE EYE. -THE EAR. 



1. Our sensations may be conveniently divided into 
general and special sensations. General sensations are 
such as hunger, thirst, fatigue, restlessness, nausea, pain, 
pleasure, ease. 

2. The general sensations are not limited to any one 
part of the body, nor have they any special organ. 

3. The special sensations are touch, taste, smell, sight, 
and hearing. Each of these has a special organ. 

General Sensations. 

4. Hunger is referred chiefly to the stomach, but the 
sensation is by no means confined to that organ. It is 
a general craving of the whole body. 

5. The same may be said of thirst. These are two 
of the most imperative sensations. Most people are ren- 
dered uncomfortable by the loss of a single meal. When 
the fast is extended throughout a day or more, the desire 
becomes more urgent. In times of famine it becomes a 
passion, which may lead men to act as though bereft of 
reason. Thirst is even more distressing than hunger. 

6. These sensations are the forces that to a large 
extent direct the lives of men. The immediate object to 
be gained by daily work is to supply our bodily wants. 



PHYSIOLOGY AND HEALTH. 189 

Men could not be trusted to do the work necessary to 
keep their bodies well nourished, if they were not im- 
pelled by a craving for food. 

7. Fatigue may be felt in the muscles, or the head, 
or the spinal cord, or it may be a general feeling. It 
indicates that the body needs rest, or that it is in an 
unhealthy condition. 

8. Restlessness or nervousness may be felt all over 
the body. It shows a tired or unhealthy state of body or 
mind, and sometimes both. 

9. Nausea seems to center in the stomach, and yet it 
is an affection of the whole body. 

10. Pain is generally distinctly localized. The nerves 
are more numerous in the skin than elswhere. The inter- 
nal surfaces and organs are not so sensitive. 1 But most 
of the internal organs may be the seat of severe pain. 

11. The nerves ending in the skin are, as it were, 
the sentinels on the outpost, whose duty it is to warn the 
brain of any approaching harm. The sense of pain is 
closely allied to the sense of touch, and has almost as 
good a claim to be regarded as a special sense. 

12. There are certain general sensations of pleasure 
or comfort, such as those which follow eating, drinking, 
and resting. They follow exercise of the muscles and 
whatever heightens vital action in any part. 

13. If we study the general sensations, we find that 
they are all designed to serve some purpose. Hunger 
and thirst are the means by which the nourishment 
of the body is secured. We should often neglect to eat ; 
the great army of workers, who are constantly engaged in 

1 In surgical operations, cutting the skin and sewing it, cause 
more pain than much more extensive cuts in the deep parts. 



190 UNION SERIES, NO. 3. 

preparing in some way for the next meal, could scarcely 
be kept at work but for the constantly recurring and 
urgent demands of hunger. 

14. Fatigue is the restraining hand of nature holding 
us back from over-exertion. When we have used the 
brain, nerves, and muscles as much as they can bear to 
be used at one time, fatigue impels us to stop and rest. 
Were it not for this we might go on toiling at some ab- 
sorbing labor until we had done ourselves lasting injury. 
We must often work when we are tired ; but it should be 
our aim to vary our occupation, so that we shall not 
be excessively fatigued at any time. However tired we 
may be at night, if we find ourselves rested and refreshed 
in the morning we are safe. But if we awake weary after 
a night's rest, and each day adds to our feeling of fatigue, 
we are in danger, and we should take warning. 

15. Pain is our protection from injury. An infant 
would burn his hand off in a flame if it did not hurt 
him. Children are educated to take care of their bodies 
by the sharp suggestions of pain. Grown people are 
warned by pain in the same way. Pleasure is the prevail- 
ing condition of living things. Nature inflicts pain for 
our good. Blows or cuts that come suddenly, without giv- 
ing time enough for escape, are generally painless. In- 
juries that are immediately fatal are generally painless. 
An attack of colic causes more distress than many a mor- 
tal disease. In many, although not in all cases, w T here 
pain can serve no purpose, it is absent. 1 

1 " After a certain degree of pain, every new breach that death 
opens in the constitution, nature kindly covers with insensibility/' 
says the Vicar of Wakefield. Every one who has seen many 
deaths knows this to be in general true. 



PHYSIOLOGY AND HEALTH. 191 

16. Sensations of bodily comfort and pleasure have a 
design as well as those of pain. They naturally accom- 
pany a condition of health, the exercise of our faculties, 
and the satisfaction of natural wants. They stimulate 
us to activity and to proper attention to our daily 
necessities. 

17. These bodily sensations of pleasure should not 
be made an object in life. Those who so regard them 
are indolent, because they desire the pleasure of idle- 
ness ; they are gluttonous and intemperate, because they 
desire the pleasure of eating and drinking to excess. 
They indulge their appetites far beyond their needs for 
pleasure. Such persons are called sensualists, and their 
course of living is always injurious alike to body and 
mind. It is against nature. 

II 

Special Senses. 

1. The whole surface of the body possesses the sense 
of touch, and so does the lining of the mouth. Other 
cavities of the body have it but slightly, or not at all. It 
is most acute in the tip of the tongue and in the tips of 
the fingers. On the ends of the nerve-fibers, in some 
situations, are little round bodies, called touch corpuscles, 
which are organs of the sense of touch. 

Taste. 

2. The nerves of taste end in the tongue and palate. 
The sense is not acute in the end of the tongue. 

3. There are four distinct tastes, — sweet, sour, salt, 
and bitter. Many of the sensations that we call tastes 



192 UNION SERIES, NO. 3. 

are really smells. A morsel of food sends an exhalation 
up through the throat to the nose, and the perception 
of this is confounded with the genuine taste. Flavors 
and savors are appreciated by the sense of smell quite as 
often as by the taste. Repulsive medicines of some kinds 
may be taken more easily if the nostrils are closed while 
swallowing them. 

4. To taste any substance it must first be dissolved 
in order to be absorbed by the membrane of the mouth, 
and so come in contact with the ends of the nerves of 
taste, which lie in that membrane. Insoluble substances 
are tasteless. 

Smell. 

5. The nose is the organ of smell as well as of respira- 
tion. Anatomically, the nose is not simply that promi- 
nence on the face to w r hich in ordinary usage the name 
is limited. It includes also the nasal cavities, which 
extend back two or three inches (5 to 7.5 c - m -) and open 
into the upper part of the throat. 

6. The nasal cavities are quite narrow, separated by 
a thin vertical wall in the center, and are lined with a 
soft, moist membrane. To the membrane lining the roof 
and upper portions of these cavities the olfactory nerve 
is distributed. 

7. We perceive by smell only gaseous exhalations from 
odorous bodies. These are absorbed by the moist mem- 
brane, and so reach the nerve endings. The stream of 
air used for breathing usually passes through the lower 
part of the nasal cavities, — the odorous gases reach the 
upper part by diffusion. When we wish to smell any 
thing we " sniff," — that is, we draw in forcibly a stream 
of air, which at once reaches the membrane of smell. 



PHYSIOLOGY AND HEALTH. 



193 



8. Colds and catarrhs blunt the sense of smell, by 
thickening the membrane and by covering it with an 
impenetrable coating of mucus. 




The Eye. 

9. We regard the eye and the ear as chief among 
our sense organs, because they give us so much of our 
knowledge of the world around us. A person who is 
blind or deaf is separated completely from many of the 
pleasures and activities of 
life, and one who is bereft 
of both sight and hearing 
has a lonely existence in- 
deed. 

10. The eyeball is nearly 
spherical, and is situated 
in a cavity in the skull 
called the orbit. This cavity, w 7 hich is much larger 
than the eyeball, is well padded and lined with fat, 
which supports the ball in its place. 

11. Just above the orbit are the arching eyebrows. 
These prevent the drops of perspiration which on hot 
days roll down the forehead from running into the eyes. 

12. The eyelids are curtains of skin lined with mucous 
membrane, and stiffened by diminutive plates of carti- 
lage, They are opened and shut by muscles attached. 

13. The eyelashes on the edges of the lids make a light 
and ornamental extension of the curtains, and are useful 
to keep out an excess of light or dust from the eyes. 

14. On the edges of the lids are the openings of some 
little glands that discharge an oily substance. When the 



194 UNION SERIES, NO. 8. 

lids are inflamed this discharge becomes excessive, and 
drying, sticks them together during sleep. In health the 
discharge is just sufficient to keep their edges moistened 
and smooth. 

15. A little almond-shaped body, lying under the roof 
of the orbit, is called the tear-gland. It has about a 
dozen little tubes, from which the tears flow out and 
spread themselves over the surface of the eye. When 
for any reason the tear-gland does not work, the eye feels 
dry and hot. The lids chafe it unpleasantly, in opening 
and closing, and it becomes inflamed. The tears are 
carried off through two small holes, one in the edge 
of each lid, near the inner angle. These open into two 
canals, which run towards the nose, and empty close 
together into the lachrymal sac. From the lachrymal 
sac the nasal duct passes down about three quarters of an 
inch (15 mm ) and opens into the nose, where the tears 
are finally discharged. 

16. The tear-gland is controlled by nerves which are 
connected with the brain. Feelings of sorrow, mortifica- 
tion, and sometimes of joy, cause an influence to pass 
along these nerves, which increases the activity of the 
gland. The tears flow freely, and pass down through 
the duct and into the nose. But in weeping the water 
cannot all pass off by these natural channels. Some of 
it runs over the eyelids and rains down the face. 

17. The eyeball is a kind of camera obscura, like the 
box used by photographers in taking pictures. Its outer 
covering is a strong membrane, bluish-white in color. 
This is the " white of the eye." A thin, transparent 
membrane, shaped like a watch-glass, is set in front of 
the ball. This is the cornea. 



PH YSIOLOG Y A ND HEA L TH. 



195 







18. Behind the cornea is the colored part of the eye, 
called the iris, with the round black hole, the pupil, in 
the center. The pupil admits the light into the interior 
of the eye. The iris contains muscular fibers ; some run- 
ning out from the 
center, like the 
radii of a circle, 
some surround- 
ing the pupil. 
When the radi- 
ating fibers con- 
tract, the pupil 
is made larger. 
When the cir- 
cular fibers con- 
tract, the pupil is made smaller. We may see the pupil 
enlarge when the light is dim, and grow small in the 
bright sunshine. We have no control over these muscu- 
lar fibers. The iris is a self-regulating screen. Light and 
some other influences make it change itself. This is 
done by the agency of the nerves. 

19. Back of the pupil is the crystalline lens. This is 
a disk-like body, with the surfaces convex. It is about 
one-third of an inch (l cm ) in diameter. It is well named 
crystalline, for it is clear and transparent as the purest 
crystal. It is but little firmer than jelly. Its use is to 
bring the rays of light, which pass through it to a focus 
on the retina, just as you have seen a glass lens (burning 
glass) bring the rays of the sun to a focus, so that they 
would burn paper. In the disease called cataract, the 
crystalline lens becomes hard and opaque, and some of 
the light cannot pass through it; the power of vision 
is thereby lost. 



196 UNION SERIES, NO. 3. 

20. The eyeball behind the lens is filled with a semi- 
liquid matter, very clear, called the vitreous (glass-like) 
humor. 

21. The retina is a membrane lining the back of the 
eyeball containing the terminal fibers of the optic-nerve. 
The optic-nerve enters at the back of the ball, and after 
passing through its outer coats, its fibers spread out in 
the lining membrane. 

22. When you sit for your photograph a picture of 
your face is made upon the sensitive plate, which the 
photographer slips into the back of his camera. So when 
the eye is directed to any object, that object is pictured 
on the retina. As the rays reflected from your face pass 
through the glass lens, and fall upon the sensitive plate, 



Normal eye, in vision at long distances. 




so rays pass from the object of vision through the lens of 
the eye and the vitreous humor, and by these are brought 
to a focus on the retina. The lining of the camera is 
always of a dark color ; the retina is also of a dark color. 
The picture, both on the sensitive plate and on the retina, 
is upside down, but for some reason which we do not 
understand, it does not appear so to the mind. 

23. It is not the eye that sees, for however perfect 
the eye, if the optic nerve behind it is cut off, there is 
no vision. It is the brain that sees; but the rays of 
light which focus on the retina and make this picture 



PHYSIOLOGY AND HEALTH. 197 

stimulate the peculiar endings of the nerve-fibers which 
compose the retina, and these fibers carry an impression 
into the brain, which is vision. 

Near-Sightedness. 

24. In a perfect eye the rays of light are brought 
to a focus precisely on the retina, and a distinct picture 
is formed. Some eyeballs are too long from before 
backward. In these eyes the retina is too far from 
the lens. The rays of light focus before they reach it. 
They then cross and spread out on the retina, making 
a blurred image. Such eyes are called near-sighted, 
because objects held very near to the eye are seen dis- 




Short-sighted eye, in vision at long distances. 

tinctly, and no others. When an object is very near to 
the eye, the rays of light reflected from it come to a focus 
farther from the lens than when it is at a distance. Near 
objects are therefore distinctly pictured on the retina of 
these long eyes, while distant objects are not. Near-sight- 
edness is corrected by the use of spectacles with concave 
glasses. These glasses change the direction of the rays 
of light, so that they do not come to a focus until they 
reach the retina. 

Far-Sightedness. 

25. Some eyeballs are too short from before backward. 
The retina is too near the lens. The rays of light reach 



198 UNION SERIES, NO. 3. 

the retina before they have come to a focus, and thus a 
blurred image is formed. Such eyes are called far-sighted, 
because objects at a distance form a more distinct image 
than near objects. Rays of light from a distant object 



^^ — >■ 



-e- 




Far-sighted eye, in vision at long distances. 

come to a focus nearer to the lens than those from a near 
object. Convex glasses are the remedy for far-sighted- 
ness. They change the direction of the rays, so that they 
will focus on the retina. 

26. Near-sighted people do not as commonly have 
pain in their eyes as far-sighted people. Inflammation 
of the eye and headaches are frequently caused by this 
latter defect. That is because the far-sighted eye can 
by an effort change its shape so as to correct its defect. 
Making this effort constantly, the eye becomes fatigued 
and irritated, and the neighboring nerves sympathize. 
Those who have near-sighted eyes cannot remedy their 
defect in this way, and make no effort to do so. 

27. Children are frequently " far-sighted," and suffer 
from headaches after studying. When this takes place, 
it is wise to have the eyes tested by an oculist, 

Old-Sight. 

28. After forty years of age, the lens loses its elasticity 
and cannot focus for near objects easily. Distant objects 
may be seen clearly, but for reading or other close work 



PHYSIOLOGY AND HEALTH. 199 

convex glasses must be used. This is called old-sight, and 
does not imply any imperfection in the shape of the eye. 

29. If there is any reason to suspect that the eyes are 
imperfect they should be tested by an oculist, and the 
oversight corrected as soon as possible. It irritates and 
wearies and weakens an eye to contend with its defects. 

Care of the Eyes. 

30. The eye is worthy of more care and thought than 
some other organs, because it is so delicate and so valu- 
able. Those whose occupation requires close use of the 
eyes should be especially careful of them. The following 
suggestions are important: — 

(a) As to light, — the light should be sufficient. It 
strains and tries the eyes to read with a dim light, 
and above all, with a fading light — like twilight. School- 
rooms and offices should have plenty of window-space. 
It should equal from one-sixth to one-third of the 
floor area. The light should not be too glaring. AVhen 
it is strong, it should be tempered by shades or blinds. 
The light should fall, if possible, over the shoulder. For 
writing it should fall over the left shoulder The shadow 
of the hand will not then be thrown upon the point of 
the pen. The light should be steady, — a flickering 
light is very trying. / 

(b) It is bad to read when lying down. 

(c) It is bad to read when in motion, as when riding. 
The constant movement of the type stimulates the eye 
to follow it, by a constant movement of its ow r n, which is 
wearisome. 

(d) It is bad to read or write when the eyes are tired. 
A smarting of the lids, a feeling as of sand in the eye, 



200 



UNION SERIES, NO. 3. 



and an aching of the eyeballs are symptoms which call 
for rest. 

(e) Any trouble with the eyes should be brought to 
the notice of a physician. 



The Ear. 

31. The essential part of the ear lies deep in one of 
the bones of the skull. The flexible appendages, which 

we call the ears, are only the 
open ends of two tubes that carry 
the sound inward to the drum. 
These tubes are an inch (2.5 c - m> ) 
long. The outer half is made 
of cartilage; the inner half of 
bone. 

32. At the end of these tubes 
the drum-head is stretched 
across the passage. This is a very 
thin membrane which vibrates 
as the waves of sound strike it. 

33. Behind the drum-head lies the shallow cavity, 
called the drum or middle ear. In order that a drum- 
head may vibrate freely, and make a clear sound, there 
must be a hole in the side of the drum. In the drum 
of the ear this necessity is provided for by a tube (the 
eustachian tube) passing from the ear to the throat. A 
cold in the head or a chronic catarrh will sometimes close 
this tube. Deafness results, which is relieved often very 
suddenly, when the tube is opened. 

34. The drum contains three little bones (the small- 
est in the body), united by joints in a chain, which is 






PHYSIOLOGY AND HEALTH. 201 

attached at one end to the inside of the drum-head : at 
the other end to a membrane which covers a passage- 
way to the inner ear. As 
the drumhead vibrates, the 
motion is imparted to these 
bones, and carried by them 
to the inner ear. These 
bones are not absolutely 
essential to hearing. Per- 
sons who have lost the drum-head and the little bones 
can still hear, but not well. 

35. The internal ear is lodged in a bone, w T hich, 
because it is so hard, is called the petrous bone (petros, 
a stone). The external and middle ear serve to con- 
duct sound to the internal ear. Here is the ending of 
the auditory nerve that receives the impression of sound. 
If the auditory nerve is cut no sound is heard, though 
the ear is uninjured. It is the brain that hears, and 
not the ear. 

36. Sound is a vibration that can be recognized by the 
ear. Fishes have no external ear. The vibrations are 
conveyed through the bones of the head to the nerve end- 
ing in the internal ear. They may be carried to our ears 
in the same way. Audiphones and similar instruments 
held between the teeth are set in vibration by sound ; 
the vibration is sent through the teeth and skull to the 
internal ear. This kind of hearing is not at all acute, 
but better than none. 

37. These instruments are useful only when the deaf- 
ness results from obstruction in the external or middle 
ear. If the internal ear alone is defective they are quite 
useless. 



202 UNION SERIES, NO. 3. 

Care of the Ear. 

38. The best way to take care of the ear is to let it 
alone. No one should put any instrument into his ear 
for cleaning or any other purpose. There is danger of 
irritating and injuring it. 

39. It may be gently syringed out with warm water, 
if necessary. If any thing lodges in the ear, it should 
be removed by a physician. A soft towel and the ends 
of the fingers will suffice to keep it clean. 

40. The ears should never be boxed. The drum mem- 
branes may be ruptured in this way. 

41. It is wise in cold, windy weather to put a bit of 
cotton into the ear to protect it. This is especially im- 
portant for those who are subject to catarrh, or are in 
delicate health. 

42. Any one who has a constant discharge from the 
ear should consult a physician about it without delay. 

Effects of Alcohol upon the Senses. 

43. All the senses are more or less dulled by the action 
of alcohol upon the nerves. If alcohol is taken habitu- 
ally, its blunting effect is a constant menace to the senses. 
The organs of taste that are frequently subjected to the 
irritating effects of alcohol or tobacco become incapable 
of tasting delicate flavors. Food for such a person must 
be highly seasoned, or he pronounces it tasteless and not 
" fit to eat." The sight may become dimmed by the use 
of alcohol and tobacco, and blindness result. Abstinence 
from both is followed in most cases by the restoration 
of the eye-sight. 



PHYSIOLOGY AND HEALTH. 203 

ILLUSTRATIONS. 

1, The eye of an ox or some other animal from the butcher will 
illustrate the structure of the human eye. Point out the cornea, 
iris, and pupil. Cut the ball open, and show the lens, the vitreous 
body and the retina. 

2. The internal ear may be shown by a careful section of the 
temporal bone, in which it is situated. 



QUESTIONS. 

I 

I, 2, 3. Into what two classes may sensations be divided ? What 
are general sensations? What are special sensations and where 
are they located? 

4, 5. To what part of the body is the sensation of hunger re- 
ferred? of thirst? Which is the more urgent? 

6. How do hunger and thirst keep the world active? 

7, 8, 9, 10. What is the location of fatigue ? of restlessness ? of 
nausea? of pain? 

II. Why should the nerves of pain be more numerous on the 
surface than in the interior of the body? 

12, 13, 14, 15. Wliat purpose is served by the sensations of 
hunger and thirst? of fatigue? of pain? 

16. Have pleasurable sensations a design? 

17. Should pleasurable sensations be made an object in life? 
What is a sensualist? 

ii 

1. What is the organ of touch? 

2. What is the organ of taste? 

3. What are the tastes ? What has the nose to do with taste? 

4. In what condition must a substance be in order to be tasted ? 

5. 6. Describe the nasal cavities. What is the nerve of smell 
called? 

7. In what condition must a body be in order that we may 
smell it ? 

8. How do colds and catarrh blunt the sense of smell? 



204 UNION SERIES, NO. 3. 

9. To which of our sense organs do we give the first place? 

10, 11, 12, 13, 14. Describe the orbit ; the eyeball ; the eyebrows; 
the eyelids ; the eyelashes ; the glands of the lids. 

15. Where do the tears come from? Where do they go? 

16. How is the action of the tear-gland controlled? 

17. What instrument is like the eye in structure ? What is the 
cornea? 

18. What is the iris? the pupil? How is the size of the pupil 
changed ? 

19. What is the lens? What is a cataract? 

20. What is the vitreous humor? 

21. What is the retina? 

22. In what respect is vision like taking a photograph? 

23. Is it the eye that sees ? 

24. What is near-sightedness ? 

25. What is far-sightedness? 

26. Who suffer most from pain and discomfort in the eyes, — 
near-sighted or far-sighted people ? 

27. Name one effect of far-sightedness. 

28. What is " old sight"? 

29. Why should an oculist be consulted if the eye is defective ? 

30. Give five rules for the care of the eyes. 

31. Where is the essential part of the ear? What is the use of 
the part which is in view? 

32. What is the drum-head? 

33. What is behind the drum-head ? What is the " hole " in the 
drum ? 

34. Describe the bones of the ear and their use. 

35. How is the internal ear protected? Does the ear hear? 

36. What is sound? How do fishes hear? 

37. How are audiphones useful? 

38. How shall we take care of the ear? 

39. What should be done if anything lodges in the ear? 

40. Why is it wrong to box the ears? 

41. 42. What precaution should be taken by those who have 
sensitive ears ? 

43. How does alcohol affect the senses? 



INDEX. 



Absorption, 72, 73. 
Abstinence, 44. 
Adam's apple, 107. 
Air, bad, 82. 
11 changes in, 103. 
" composition of, 102. 
Alcohol, 16, 34, 41. 
11 action of, 30. 
11 effects on bones and joints, 
137. 
Alcohol, effects on heart and blood- 
vessels, 97. 
Alcohol, effect on the lungs, 118. 
" effect on the senses, 202. 
" effects on the stomach, 65. 
" effects on the skin, 185. 
" and the muscles, 151. 
" not a food, 29. 
" a narcotic poison, 42. 
" origin of, 37. 
11 a poison, 82. 
" effects on the nerves, 167. 
Alcoholic appetite, 42. 

consumption, 119. 
drinks, inheritance from, 
170. 
Alcoholic fermentation, 41. 
Alimentary canal, 52. 

" appendages to, 52. 
11 divisions of, 52. 
" " length of, 52. 

Anatomy, 8. 
Aorta, 89. 



Apparatus, circulatory, 85. 
Assimilation, 51, 78. 

Bathing, 184. 
Beans, 24. 
Beaumont Dr., 66. 
Bedroom, 14. 
Beef, 23. 
Beer, 46. 
Bile, 61. 
Blood, the, 74. 

11 amount in the body, 85. 

11 coagulation of, 78. 

11 changes in the, 114. 

11 corpuscles, 75. 

" pure and impure, 81. 
Blood-vessels, work of, 88, 92. 
Bodily heat, 177. 
Bone, 123. 

" collar, 130. 

11 constitution of, 124. 

11 formation and growth of, 125. 
Brain, hemispheres of the, 161. 

" the human, 160. 
Bread, good, 27. 

" heavy, 27. 
Breathing, 111. 
Bronchi, the, 109. 

Capillaries, 85, 94. 
Cake, 27. 

Carbon dioxide, 103. 
Carpus, 131. 

205 



206 



IXDEX. 



Cartilages, costal, 129. 

Cataract, 195. 

Catarrh, chronic, 119, 200. 

Chemical elements in the body, 18. 

Chest, the, 112. 

Chords, vocal, 107. 

Chyme, 64. 

Cider, 45. 

" drinking, 45. 
Cilia, 143. 
Circulation, pulmonary, 90. 

" regulation of, 95. 

Clothing, 180. 
Cocoa, 34. 
Coffee, 34. 
Colds, 118, 184. 
Column, spinal, 127. 
Cold-blooded animals, 179. 
Consumption, 119. 
Cooking, 25. 

Cord spinal, 126, 160, 164. 
Corn, 23. 
Corpuscles, red, 75, 114. 

" white, 75, 142. 

11 work of red, 76. 

Crystalline lens, 195. 
Cuticule, the, 174. 



Decay, cause of, 38. 
Delirium tremens, 14, 119. 
Dermis, 174. 
Diaphragm, the, 57, 112. 
Digestion, 62. 

" rules for good, 68. 

Disease, germs, 33. 
Distillation, 47. 
Drinks, natural, 31. 
Drum-head, the, 200. 
Duct, right lymphatic, 80, 

" thoracic, 80. 
Duodenum, 64. 
Dyspepsia, 57, Q6, 68. 



Ear, the, 200. 
" care of the, 202. 
" the internal, 201. 
Eating and drinking habits, 28. 

" " " object of, 15. 

Eggs, 23. 
Emulsion, 64. 
Epidermis, the, 174. 
Eustachian tubes, 106, 200. 
Exercise, 166. 

11 for girls, 150. 
" rules for, 149. 
Eye, the, 193. 
Eyes, care of the, 199. 

Fainting, treatment for, 86. 
Far-sightedness, 198. 
Fatigue, 190. 
Fats, 25. 

Fatty degeneration, 152. 
Femur, 132. 

Fermentation acetous, 46. 
" vinous, 46. 

Ferments, 38, 40. 
Fibula, 133. 
Fish, 23. 

Food, elements in, 19. 
Foods, animal, 22. 

" nitrogenous, 21. 

" non-nitrogenous, 21. 

11 vegetable, 23. 

Gains, daily, 10. 
Gall-bladder, the, 61. 
Gastric juice, 58, 63. 
Germs, 38. 
Glands, 53. 

" sebaceous, 183. 

" lymphatic, 81. 

" salivary, 58. 

" sublingual, 60. 

11 submaxillary, 59. 

11 sweat, the, 181. 



IXDEX. 



207 



Glottis, the, 107. 
Glycogen, 61. 
Grains, 23. 
Gullet, the, 57. 

Hair, the, 175. 

Health, 8. 

Health, science of, 8. 

Heart-beats, number of, 93. 

Heart, 87. 

11 muscles of the, 148. 

11 palpitation of the, 92. 

" the smoker's, 92. 

" sounds of the, 91. 

" valves of the, 88, 90. 

11 work of the, 90, 92. 
Heat, sources of, 179. 
Humerus, 131. 
Hygeia, Hygiene, 8. 

Ice-water, 69. 
Indigestion, 69. 
Infusoria, 122. 
Inhibitory nerve, the, 96. 
Inorganic substances, 20. 
Intemperance, cause of, 48. 
Internal combustion, 181. 
Intestine, large, 58. 
11 small, 58. 

Iris, the, 147, 195. 

Jaundice, 61. 
Joints, the, 134. 
Joint-water. 136. 
Juice, gastric, 63. 
Juice, intestinal, 65. 

Lacteals, 80. 
Larynx, the, 107. 
Ligaments, 135. 
Liquors, lighter, 44. 
Liver, the, 60. 

11 gin-drinker's, 67. 



Losses, daily, 10. 
Lungs, the, 105. 

" blood-vessels of the, 109. 
Lymph, 81. 
Lymphatics, 79. 

Metacarpus, 131. 

Metacarpal bones, 131. 

Metatarsus, 133. 

Milk, 22, 34. 

Mineral substances, 28. 

Molds, 38. 

Motion, organs of, 143. 

" power of, 142. 
Mouth, the, 53. 
Mucous membrane, 53. 
Muscle-fibers, 144. 
Muscles, involuntary, 146. 

11 voluntary, 143. 
Muscular exercise, 148. 

Nails, the, 175. 

Narcotics, effects on blood, 82, 134. 

Near-sightedness, 197. 

Nerves, the, 158. 

work of the, 163. 
Nerve-centers, 160. 
Nervous prostration, 13. 

" system, the. 158. 
Nicotine, 82, 152, 171. 
Nose, the, 105. 

Oats, 23. 

Object of this book, 8. 

Old-sight, 199. 

Optic nerve, 196. 

Organs, 7. 

Organic substances in the body, 21. 

Ossa innominata, 132. 

Over-excitement, 167. 

Oxygen, 104. 

Oyster, the, 23. 



208 



INDEX. 



Pancreas, the, 61. 
Pancreatic juice, 62. 
Papillae, 176. 
Parotid glands, 59. 
Pastry, 27. 
Peas, 24. 
Pelvis, 132. 
Peptone, 64. 
Perspiration, 9. 
Phalanges, 131, 133. 
Physiology, 8. 
Plants, food of, 38. 
" work of, 20. 
Plasma, the, 77. 
Pleura, the, 111. 
Pleurisy, 111. 
Poisons, 34. 
Poisoning, lead, 33. 
Potato, the, 24. 
Pulse, the, 93. 
Pupil, the, 146, 195. 
Pylorus, 58. 

Radius, 131. 

Ration, daily, 29. 

Repair, 16. 

Respiratory apparatus, 105. 

" muscles, 112. 

11 passages, 105. 

Retina, 196. 
Ribs, 129. 
Rice, 23. 

Sacrum and Coccyx, 132. 
Saint Martin, 66. 
Sartorius, 145. 
Saliva, 60. 

Sensations, general, 188. 
Senses, special, 191. 
Shoulder-blade, 130. 
Skin, the, 174. 
Sleep, 13, 166. 

" inability to, 13. 

" means of inducing, 13. 

" time for, 13. 



Sleeping-rooms, 116. 
Smell, the sense of, 105, 192. 
Snoring, 106. 
Sound, 201. 
Spinal column, 127. 
Spinal cord, 126, 160, 164. 
Spine, curvature of the, 128. 
Sprain, a, 136. 
Stomach, the, 53, 57. 

" lining of, 57. 
Sugars, 25. 
Synovial membrane, 136. 

Tarsus, 133. 
Taste, 191. 
Tea, 34. 
Teeth, care of, 55. 

" not bones, 55. 

11 first set, 54. 

" second set, 55. 
Tendon of Achilles, 146. 
Tendons, 145. 
Throat, the, 56, 106. 
Tibia, 133. 
Tobacco, 34, 119. 

" effect on the lungs, 118. 
Tongue, the, 56. 
Touch, sense of, 191. 

Ulna, 131. 

Valves, semi-lunar, 91. 
Veins, valves of the, 88. 
Ventilation, 114. 
Vertebrae, 127. 
Villi, 74, 80. 
Vinegar, 46. 
Vitreous humor, 196. 
Voice, the, 117. 
Voice-box, 117. 

Water, 16, 31. 
Wheat, 23. 
Windpipe, the, 107. 
Wine, 41, 48. 



